• Elastomers and Composites
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• v.47 no.2
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• pp.148-155
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• 2012

EPDM, IIR, and BIIR composites were thermally aged and the crosslink density changes were investigated. Crosslink densities of the EPDM composite increased with increasing the aging time and temperature, whereas those of IIR and BIIR composites for long-term aging at high temperatures tended to decrease. Activation energies for the crosslink density changes of the EPDM composite were higher than those of the BIIR one. The experimental results were explained with the number of allylic hydrogens, activation of the zinc complex, the steric hindrance effect, and oxidation of rubber chain.

• Elastomers and Composites
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• v.47 no.2
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• pp.156-161
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• 2012

Difference in recovery behaviors from the circular deformation of natural rubber (NR) composites aged in air and distilled water, respectively were investigated. Recoveries of the samples aged in air were larger than those of the samples aged in distilled water. Recovery rates of the samples reinforced with filler were faster than those of the unreinforced ones. Recovery rates of the carbon black-filled samples were faster than those of the silica-filled ones. Difference in the recovery behaviors according to the aging media can be explained by the crosslinking density changes and the annealing effect.

• The Journal of the Korea Contents Association
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• v.11 no.12
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• pp.832-843
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• 2011

This quasi-experimental study examined the effect of the a senior simulation program and following group discussion on the anxiety about aging. The senior simulation program did not raise the level of four factors of the anxiety about aging. The item of fear of losing friends when becoming old was the only significant one with increased level of anxiety. Discussion session for sharing the simulation experience revealed a positive effect of decreasing anxiety level in the factor score of fear of old people, the item of liking getting together with elders, and the item of liking to do something for elders. With the help of information technology.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.29 no.1
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• pp.27-44
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• 2003

전반적인 피부세포의 생리적 지능 자하로 인한 자연노화와 더불어, 여러 피부 스트레스 요인들이 다양하게 작용하여 발생하는 외인성노화를 방지하거나, 개선할 수 있는 항노화소재로서의 개발 가능성을 알아보기 위해, 예로부터 항염활성이 있다고 알려진 oleanolic acid(OA)를 포함한 ursolic acid(UA), betulin, betulinic acid(BA) 등의 triterpenoids가 어떻게 피부에서의 항노화 활성을 나타내는지를 알아보았다. 시험 결과, OA는 자외선에 의한 각질형성세포에서의 PGE$_2$ 생성과 섬유아세포(NHF)에 의한 matrix metalloproteinase-1(MMP-1) 분비를 억제하였다. 그리고, NHF의 procollagen 생성을 촉진하였으며, 이런 procollagen 생성촉진활성이 in vivo에서도 발현되는 것을 무모생쥐의 실험을 통해서 확인하였다. 또한 OA는 각질세포의 증식과 분화를 촉진하여 표피세포로 하여금 세라마이므와 필라그린 생성을 증가시키도록 하는 작용도 있음을 보여주었다. 더불어 실험한 UA, betulin, BA 들은 비록, betulin, BA의 경우 세포 독성이 다른 물질 들에 비해 높았고, UA가 각질세포의 분화를 오히려 억제하는 양상을 보이기는 했지만, 대부분의 기능은 OA와 유사하였다. 피부세포보호작용과 진피 기질물질에 대한 작용, 그리고, 표피의 장벽기능과 보습기능에 대해 시험한 본 연구는, 식물성분인 triterpenoids가 피부를 위한 항노화소재로서의 개발 가능성이 있음을 확인하는 계기가 되었고, 그 중에서도 OA가 보다 우수한 항노화 소재가 될 수 있음을 시사하고 있다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.10
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• pp.1320-1325
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• 2007

Retarding retrogradation of a Korean rice cake (Karedduk) added with carbohydrate materials after $0{\sim}30hrs$ of storage at $5^{\circ}C$ were investigated by Avrami equation using textural characteristics. Carbohydrate materials such as powdered sugar, trehalose, fructooligosaccharide (95%), isomalto, healtholigo, and galactooligo-saccharide (50%) were added in 0, 1, 5 or 10% levels on dry rice flour. In the amylogram, the breakdown (P-H) and consistency (C-H) for Karedduk added with carbohydrate materials were lower than those of the control. Decrease in the Avrami exponent (n) and increase in the time constant (1/k) of Karedduuk added with carbohydrate materials during storage determined by Avrami equation were important comparison factors to the control in terms of retrogradation rate analysis. The Aurami exponent (n) for control, fructooligosaccharide (95%) 10% and healtholigo 1% addition were 2.415, 1.977 and 3.297, respectively. The time constant (1/k) for fructooligosaccharide (95%) 5% and healtholigo 1% addition were lower than thecontrol. Lastly, Karedduk added with carbohydrate materials, except for fructooligosaccharide (95%) 5% and healtholigo 1% addition, was effective in retarding retrogradation.

• 한국노년학
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• v.36 no.4
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• pp.1109-1124
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• 2016

We examined the effect of stereotype threat (STT) on spatial working memory and facial emotion recognition in Korean elderly. In addition, we investigated the role of expected moderator such as self-perception of aging. Seventeen seniors (male=7) received basic cognitive tests including K-WMS-IV, MMSE and answered self-report questionnaires including self-perception of aging, anxiety of aging, attitude toward aging and age identity on the first visit. On the second visit, they were exposed to negative stereotype by reading a script detailing cognitive decline related to aging while a control group was exposed to a neutral content. Following the exposure, they were tested on a spatial-working memory task (Corsi-block tapping task) and emotion recognition task (facial expression identification task). The results showed that the seniors exposed to STT showed significantly lower performance on emotion recognition task (p < .05) (i.e., especially on the more difficult facial stimuli). In addition, there was a significant interaction between STT and self-perception of aging (p< .05), indicating that those who have positive self-perception of aging did not show impairment in emotion recognition task and difficult spatial working memory task under STT. On the other hand, those with negative self-perception of aging showed impaired performance under STT. Taken together, the current study suggests that being exposed to STT could negatively influence cognitive and emotional functioning of elderly. Interestingly, having a positive self-perception of aging could protect the underperformance caused by STT.

• Journal of Industrial Convergence
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• v.18 no.1
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• pp.87-96
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• 2020

The purpose of this study was to examine the dual mediating effects of growth mindset and hope between body image and successful aging of the elderly. For this purpose, we surveyed 422 elderly people in D and S city of Chungcheongnam-do, and D metropolitan city. Collected data were analysed using SPSS 25.0 and PROCESS macro 3.4 program. Frequency analysis, reliability analysis and dual mediating effect analysis by using bootstrap were performed. The results of the study are as follows. First, as a result of correlation analysis there was a statistically significant positive correlation between variables. Second, as a result of path analysis, body image had a positive effect on growth mindset and hope, growth mindset had a positive effect on hope and successful aging, and hope also had a significant effect on successful aging. Third, as a result of dual mediation effect analysis, growth mindset and hope mediated in the relationship between body image and successful aging. This study provided new models and basic data by using body image, growth mindset and hope for successful aging of the elderly.

• Korean Journal of Family Social Work
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• no.54
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• pp.187-224
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• 2016

This study aims to investigate the effect of psychosocial aging on age integration and the moderating effect of Familism and Family solidarity. In particular, this study has significance for establishing a basis of practical and political intervention in family level for improving age integration. We employed data from the 'Ageing Society Awareness Investigation' funded by Korean National Research Foundation in 2014. Our analysis sample consisted of 702 adults who were from 40 to 90 years old. Also, this study conducted descriptive statistics and multiple regression analysis by using STATA13. First of all, the lower psychosocial aging awareness is the higher age integration awareness. Familism and family solidarity were not a significant predictor for age integration. However, the interaction effects between familism as well as family solidarity and psychosocial aging ware statistically associated with age integration. That is to say that as psychosocial aging is negative, when decrease age integration, the net moderating effects of familism and family solidarity were found between age integration and psychosocial aging. Based on the results, this study provides implications that reinforcing family value and promoting interaction and solidarity with family members are positively contributed to age integration awareness at this point of negative psychosocial aging.

• The Monthly Diabetes
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• s.210
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• pp.40-41
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• 2007

과학과 문명의 발전으로 평균수명이 대폭 늘어난 지금은 오래 사는 것보다 어떻게 사느냐가 더 중요하다. 젊은 사람들에게 장수는 먼 훗날의 얘기마냥 들리고, 늙고 힘없이 오래 사는 것보다는 끝까지 젊고 질 높은 삶을 사는 것이 더 절실하다. 그만큼 사람들은 오랫동안 살아가는 것도 중요하지만 어떻게 오래 사느냐를 더 생각하게 된 것이다. 여기에 소개한 음식들은 모두 과학적으로 노화 방지 효과가 밝혀진 것들이다. 구하기 힘든 음식이나 들어보지도 못한 음식들이 아니라 평소 흔히 먹는 음식이 많이 포함되어 있다. 무조건 적으로 많이 섭취하는 것 보다 어떠한 음식이 어떻게 노화를 예방해주는 효과가 있는지 살펴보고 실천해보자.

• Journal of Life Science
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• v.10 no.3
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• pp.254-261
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• 2000

In order to observe the bioactivity of ovariectomized rats, ovariectomized group (Ovx), nonovariectomized group (Sham), ovariectomized Vitamin C-treat group (Ovx+Vit C), ovariectomized Vitamin E-treat group (Ovx+Vit E) and ovariectomized Vitamin C+Vitamin E-treat group(Ovx+Vit C+E) were made. Lipidperoxides of liver and kidney, serum total cholesterol and HDL-cholesterol were investigate as follows. Lipidperoxides of liver and kidney in Ovx group were 1.78 times and 1.61 times increased compared to Sham group respectively. But, they were significantly decreased in Ovx+Vit C group, Ovx+Vit E group, Ovx+Vit C+E group compared to Ovx group. Serum total cholesterol in Ovx group was increased 2.57 times compared to Sham group. Injections of each substance such as ascorbate, tocopherol, mixture (C+E) make data of Cholesterol become low. When especially Vit C is injected, the data of cholesterol lowed by about 94%. Serum HDL-cholesterol in Ovx group decreased 36.7% compared to Sham group. And as the result of the measurement of SOD, Catalase, and GPx which are antioxidant enzyme, SOD and Catalase activities in Ovx group much higher than in Sham group. Based on the results, it is supposed that more produced free radicals increased antioxidant enzyme. And it is also thought that vitamin can inhibit aging by reducing antioxidant enzyme.