• 대한기계학회논문집A
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• 제37권1호
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• pp.1-8
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• 2013

자동차용 냉각기 고무호스는 열과 기계적 하중을 받으면서 국부적으로 형성된 전기적 영향으로 인해 노화와 고장이 발생한다. 본 연구에서는 개선된 시험방법을 이용하여 고무호스의 파괴거동을 재현하였다. 냉각기 고무호스 재료인 카본블랙이 함유된 EPDM 고무를 사용하여 인장응력과 전기화학적 복합 스트레스를 가하여 노화거동을 분석하였다. 노화 시간에 따른 전류 및 저항의 변화거동을 관찰하였으며 인장 변형 스트레스와 전압 및 노화온도 조건에 따른 노화거동을 분석하였다. 고무 시험편을 수직면으로 정밀하게 절단하여 시험편 표면 및 내부의 변화거동을 분석하여 전기화학적 노화거동과 고장메커니즘을 규명하였다.

• 대한치매학회지
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• 제23권1호
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• pp.44-53
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• 2024

Background and purpose: The anti-aging standard forest healing program (ASFHP), which uses forest therapy, was reported to be effective in improving psychological, physical, and cognitive functions. However, there are several challenges to directly visiting the forest. This study aimed to investigate the impact of multi-session ASFHP with forest visit on the mental and physical health of the older people with visits to forest facilities and compared them with those of the same program conducted indoors. Methods: Individuals aged over 70 years with concerns about cognitive decline were recruited at dementia relief centers and divided into control and experimental groups. A total of 33 people were administered ASFHP under the supervision of a forest therapy instructor. The control group stayed indoors, while the experimental group visited a forest healing center and repeated the program 20 weeks. Results: The multiple-session ASFHP positively affected cognitive impairment screening test (CIST) total scores (p=0.002), memory (p=0.014), Korean version of the Repeatable Battery for the Assessment of Neuropsychological Status total scores (p<0.001), immediate recall (p=0.001), visuospatial/construction (p<0.001), language (p<0.001), forest healing standard questionnaire total scores (p=0.002), and cognitive function (p=0.019), regardless of location. The forest visits during the ASFHP showed positive effects on orientation (p=0.035), delayed recall (p=0.042), emotional stability (p=0.032), physical activity (p=0.005), and health (p=0.022). The CIST scores of the memory domain were the strongest indicator of the multiple-session ASFHP effects. Conclusions: The 20-week multi-session ASFHP with forest visit showed effects on cognitive improvement and physical and emotional stability compared to indoor education.

• Asian Pacific Journal of Cancer Prevention
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• 제17권sup3호
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• pp.323-335
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• 2016

Breast cancer risk assessment has developed during years and evaluation of genetic factor affecting risk of breast cancer is an important component of this risk assessment. The aim of this meta-analysis was to investigate the role of XRCC1 polymorphisms (Arg194Trp, Arg280His and Arg399Gln) in risk of breast cancer among different population and categories of menopausal status.PubMed, Medline, Web of Science, and PubMed Central were systematically searched to identify studies evaluating association between breast cancer and XRCC1 gene polymorphisms (Arg194Trp, Arg280His and Arg399Gln). Two authors independently extracted required information. Odds Ratios were pooled for four genetic inheritance models using both fixed and the DerSimonian and Laird random-effect models. Egger's test and contour-enhanced funnel plot was used to evaluate publication bias and small study effect. Additional subgroup analysis was performed for menopausal status, ethnicity, and source of controls. After evaluation and applying inclusion criteria on extracted studies, fifty three studies were included in this meta-analysis. For polymorphisms of Arg194Trp and Arg280His, no significant association was observed in all genetic models. Arg194Trp had a protective effect in post-menopausal status only in homozygote model (OR=0.57 [0.37-0.88]). Arg399Gln showed significant association with breast cancer in homozygote (OR=1.21 [1.10-1.34]), dominant (OR=1.09 [1.03-1.15]) and recessive (OR=1.21 [1.09- 1.35]) genetic models. Arg399Gln was associated with higher risk in post-menopausal status for homozygote and heterozygote models. Our findings suggest that XRCC1 gene polymorphisms modify breast cancer risk in different populations and different categories of menopausal status.

• 대한한의학회지
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• 제45권1호
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• pp.17-43
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• 2024

Objectives: Underpinned by the context of a Korean traditional medicine cohort study on healthy aging, this research primarily aims to guide the selection of Clinical Outcome Assessments (COAs) for elderly healthy aging patient registry research, offering insights into the selection process; and secondly, to streamline the resource-intensive process of obtaining permissions for validated COAs, benefiting future traditional Korean medicine clinical researchers. Methods : In this study, we identified outcomes through a review of previous studies, followed by a process involving expert consultations to select the final outcomes. Subsequently, for the selected outcomes that were Clinical Outcome Assessments (COAs) developed tools, we searched in commercial databases to confirm the availability of Korean versions and the necessity of obtaining permissions. Finally, we obtained permissions for their utilization and, when needed, acquired the original instrument questionnaire through payment. Results: Through a literature review of existing observational studies, a total of 57 outcomes were selected, with 19 of them identified as COA instruments. Upon verifying usage permissions for these 19 instruments, it was found that 17 required author-specific permissions, and among these, 2 needed a purchase as they were commercially available. Conclusion: This study provides a detailed overview of outcome selection and permission acquisition for elderly patient registry research. It underscores the importance of Clinical Outcome Assessment (COA) tools and the rigorous approval process, aiming to enhance research reliability. Continuous verification of COA information is essential, and future research should explore Core Outcome Set (COS) development through consensus-building approaches like Delphi studies.

• 대한지역사회영양학회지
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• 제15권3호
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• pp.308-328
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• 2010

As the older adult period $({\geq}65y)$ is increasing, it is needed to investigate the trend of aging-dependent anthropomeric index and nutrient intake, and establish the more specific dietary guide for the different stages of aging period. To find the difference in nutrient intake among the Koreans aged 50-64, 65-74 and 75 years and older, and also any characteristics of dwellers in longevity area, we recruited 1,083 subjects (385 male and 698 female) aged 50-95 years (mean age, 71.3 yrs) living in Kugoksoondam area (Kurye, Goksung, Soonchang and Damyang counties), known as a longevity-belt region in Jeonlaprovince, Korea. We measured some anthropometric index and collected 2 day-dietary record. Nutrient intakes were analyzed by using DW24 program. The mean height and weight of subjects aged 75 years and older were lower than Korean national reference. BMI and obesity $({\geq}25kg/m^2)$ prevalence were significantly decreasing with aging. Underweight $(BMI<18.5kg/m^2)$ prevalence was also increasing with aging, especially in males, and it was slightly higher than national average, but similar to that in some other rural area. Obesity prevalence of male subjects was lower compared to national prevalence, but abdominal obesity prevalence $(waist{\geq}80cm)$ was very high in females (about 89%). In both genders, the average proportional contribution of carbohydrate, protein and fat to energy intake was not different between 65-74 years and 75 years and older. On overall, nutrient intake and quality of diet of females were inferior to those of males so that many of females aged 75 years and older assumed to be at risk of malnourished status. Fiber, folate and vitamin E intakes were substantially higher compared to those in 2007 KNHNES and other some studies in rural area. While almost nutrient %EAR was significantly decreased with aging in females, there was no significant difference in %EAR for protein, vitamin A, $B_1$, $B_6$, $B_{12}$, niacin, Ca and Zn between 65-74 years and 75 years and older in males. Vitamin $B_2$ for male aged 50-64 years, vitamin $B_2$ and Ca for male aged 65 years and over and female aged 50-74 years, and vitamin $B_2$, vitamin C, Ca and folate intake for female aged 75 years and older were assessed to be at risk to undernutrition based on the prevalence of intake below EAR. MAR of 13 nutrients and the number of nutrients consuming below EAR were significantly decreasing with aging in both genders, however, the number of nutrients of INQ < 1 and the average mini-nutritional assessment score were not significantly different between 65-74 years and 75 years and older. Taken together, decreasing tendency of nutrients intake and the quality of diet with aging was more evident in females than in males, and it is unique that our subjects consumed substantially higher fiber, folate and vitamin E compared to not only urban but also some other rural areas.

• Journal of Chest Surgery
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• 제49권sup1호
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• pp.37-43
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• 2016

Background: While demand for cardiovascular surgery is expected to increase gradually along with the rapid increase in cardiovascular diseases with respect to the aging population, the supply of thoracic and cardiovascular surgeons has been continuously decreasing over the past 10 years. Consequently, this study aims to achieve guidance in establishing health care policy by analyzing the supply and demand for cardiovascular surgeries in the medical service area of Korea. Methods: After investigating the actual number of cardiovascular surgeries performed using the National Health Insurance claim data of the Health Insurance Review and Assessment Service, as well as drawing from national statistics concerning the elderly population aged 65 and over, this study estimated the number of future cardiovascular surgeries by using a cell-based model. To be able to analyze the supply and demand of surgeons, the recent status of new surgeons specializing in thoracic and cardiovascular surgeries and the ratio of their subspecialties in cardiovascular surgeries were investigated. Then, while taking three different scenarios into account, the number of cardiovascular surgeons expected be working in 5-year periods was projected. Results: The number of cardiovascular surgeries, which was recorded at 10,581 cases in 2014, is predicted to increase consistently to reach a demand of 15,501 cases in 2040-an increase of 46.5%. There was a total of 245 cardiovascular surgeons at work in 2014. Looking at 5 year spans in the future, the number of surgeons expected to be supplied in 2040 is 184, to retire is 249, and expected to be working is 309-an increase of -24.9%, 1.6%, and 26.1%, respectively compared to those in 2014. This forecasts a demand-supply imbalance in every scenario. Conclusion: Cardiovascular surgeons are the most central resource in the medical service of highly specialized cardiovascular surgeries, and fostering the surgeons requires much time, effort, and resources; therefore, by analyzing the various factors affecting the supply of cardiovascular surgeons, an active intervention of policies can be prescribed for the areas that have failed to meet the appropriate market distributions.

• 한국환경복원기술학회지
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• 제12권1호
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• pp.52-66
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• 2009

The increase of rice productivity, the decrease of rice demand, aging farmers, and the market-opening of rice along with the domestic and international conditions changes have been led to the increase of the abandoned rice paddy fields. Such abandoned rice paddy fields have been left in many areas and most of them have become wetlands. The purpose of this study is methodology of selection to the wetland for development in the abandoned rice paddy fields along with surroundings. The selection of habitat suitability index assessment study to conservation and restoration was done through hydrology, wild animals habitation, wetland vegetation, outside disturbance, and natural purification capacity assessment. In addition, the same method was applied to assessment items and standards for both the restoration site selection and the type of restoration. Both assessment items and standards were applied to the sites, drawn on the maps, and overlayer for the comprehensive map, and then the wetland suitability index was applied to the suitable site. The development technique was applied to 10 sites near the Banwol Stream watershed in Gunpo, Gyeonggi province. The selection of conservation, restoration, and the optimal sites can lead to not only the biodiveristy increase in agricultural or semi natural areas but also to the establishment of ecological networks in national level.

• Journal of Preventive Medicine and Public Health
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• 제56권3호
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• pp.248-254
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• 2023

Objectives: Measuring the quality of care is paramount to inform policies for healthcare services. Nevertheless, little is known about the quality of primary care and acute care provided in Korea. This study investigated trends in the quality of primary care and acute care. Methods: Case-fatality rates and avoidable hospitalization rates were used as performance indicators to assess the quality of primary care and acute care. Admission data for the period 2008 to 2020 were extracted from the National Health Insurance Claims Database. Case-fatality rates and avoidable hospitalization rates were standardized by age and sex to adjust for patients' characteristics over time, and significant changes in the rates were identified by joinpoint regression. Results: The average annual percent change in age-/sex-standardized case-fatality rates for acute myocardial infarction was -2.3% (95% confidence interval, -4.6 to 0.0). For hemorrhagic and ischemic stroke, the age-/sex-standardized case-fatality rates were 21.8% and 5.9%, respectively in 2020; these rates decreased since 2008 (27.1 and 8.7%, respectively). The average annual percent change in age-/sex-standardized avoidable hospitalization rates ranged from -9.4% to -3.0%, with statistically significant changes between 2008 and 2020. In 2020, the avoidable hospitalization rates decreased considerably compared with the 2019 rate because of the coronavirus disease 2019 pandemic. Conclusions: The avoidable hospitalization rates and case-fatality rates decreased overall during the past decade, but they were relatively high compared with other countries. Strengthening primary care is an essential requirement to improve patient health outcomes in the rapidly aging Korean population.

• 한국식품영양과학회지
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• 제41권9호
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• pp.1253-1258
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• 2012

본 연구에서는 복분자 섭취가 노화에 의한 기억력 감퇴에 개선 효과를 나타내는지 조사하기 위해 노화촉진마우스 (SAM)를 사용하여 평가하였다. 28주령 SAMP8 마우스에 복분자 시료를 100 mg/kg body weight/day로 8주간 투여한 후 수동회피시험과 수중미로시험을 실시하여 기억력 개선효과를 평가하였다. 수동회피시험에서 노화 촉진 동물(SAMP8)은 대조동물(SAMR1)에 비해 밝은 방에서 체류시간이 현저히 감소하였다. 복분자를 섭취한 노화 촉진 동물의 밝은 방에서의 체류 시간은 복분자를 섭취하지 않은 동물에 비해 현저히 증가하였다. 수중미로실험에서 대조 동물에 비해 노화 촉진 동물의 평균 탈출잠복기는 길었고, 복분자를 섭취한 경우 평균 탈출잠복기가 유의적으로 감소하였다. 뇌의 대뇌피질과 해마 조직에서 대조군에 비해 노화 촉진 동물의 acetylcholinesterase 활성이 증가하였다. 복분자를 섭취한 노화 촉진 동물의 해마 조직 내 acetylcholinesterase는 복분자를 섭취하지 않은 동물에 비해 유의적으로 감소하였다. 이 결과들은 복분자가 노화촉진마우스에서 노화에 의한 기억력 감퇴에 대한 개선 효과를 나타내며, 이는 콜린성 신경전달에 중요한 역할을 하는 acetylcholinesterase 활성 감소를 통해 이루어짐을 나타낸다. 향후 더 많은 연구가 수행 되어야 하나, 본 연구는 복분자가 노인의 기억력 개선제 개발에 좋은 기능성 소재로 활용할 수 있음을 제시한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2250-2255
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• 2011

There has been a growing interest toward railroad conjunction with opening of high-speed rail in 2004 and concurrent implementation of nation's green growth policies. Meanwhile, users' expectation on service of public transportation, especially railroad has been growing than since ever due to heightened quality of life, entering aging society, voice of equity for minorities, and greater interest in environments of communities. In order to come up with the expectations, actual improvements for user's convenience/comfort and its assessment strategies in terms of service quality level are necessary. This study defines the index of this aspect of service level as 'Sensitivity Quality'. This is conceived as one of the important factors to define travel cost as do the travel time and fare, but hardly taken into consideration when assessing a transportation system or policy-making for a transportation project. The elements included for the assessment of the sensitivity quality in this study are feeling of a ride, conformability and convenience what users feel and recognize using a train. This paper suggests that establishing sensitivity quality elements would contribute in foundation of assessing service quality and provide improved public transportation services through their scientific and objective development and management.