• 한국연초학회지
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• 제26권1호
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• pp.27-34
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• 2004

This study was carried out to examinate the effect of aging period on chromatic, chemical and organoleptic characteristics, and to evaluate of optimum aging period for each grade in flue-cured leaf tobacco. The leaf tobaccos were produced in 2000, and threshed, redried and packed in carton box under the current methods. Four grades of processed leaf(A3O, B1O, C1L and D3L) were stored during 24 months(May 10, 2001 to April 31, 2003) in warehouse of Chungju Leaf Tobacco Processing Factory. The leaf tobaccos were sampled at three month intervals for analysis of chromatic, chemical and organoleptic properties. Yellow(b), pH values and total sugar contents of four grades were significantly decreased during the aging. Filling values, tar, nicotine and CO contents of tobacco smoke, and puff number of cigarettes were not significantly changed during the aging. Positive correlation coefficients were significantly observed between taste and irritation of the calculated attributes from contents of volatile oil components in leaf tobacco and those of the panel sensory attributes. The ratio of maximum change in taste attribute was larger than that in irritation attribute during aging. The optimum aging periods estimated by taste for A3O, B1O, C1L and D3L were 17.8, 14.9, 10.8, and 9.8 months, respectively. The thin leaf(Primings and Cutters) undergo satisfactory aging earlier as compared to bodied leaf(Leaf and Tips). The results suggest that decrease of aging period for thin leaf from 18～21 to 9～12 months may be beneficial to save storage cost in flue-cured tobacco.

• 대한약침학회지
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• 제20권1호
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• pp.29-35
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• 2017

Objectives: Aging is an unconscious and gradual process that can lead to changes in biological systems. Induction of oxidative stress and apoptosis, hepatotoxicity and neurotoxicity are involved in the aging process. Regarding the antioxidant property of black seed oil, the aim of this study was to evaluate the anti-aging effect of Nigella sativa (N. sativa) oil on d-galactose-induced aging in mice. Methods: For induction of aging, D-galactose (500 mg/kg, subcoutaneously SC) was administrated to male mice for 42 days. Animals were treated with D-galactose alone or with b lack seed oil (0.1, 0.2, 0.5 mL/kg, intraperitoneally (ip)). Additionally, vitamin E (200 mg/kg) was used as a positive control. At the end of treatment, the malondialdehyde (MDA) and the glutathione (GSH) contents in brain and liver tissues were measured. Also, enzymes in serum, including aspartate aminotransferase (AST) and alanine amino transferase (ALT), were determined. The levels of the proteins Bax, Bcl2, caspase-3 (pro and cleaved) in brain and liver tissues were evaluated. Results: Administration of D-galactose (500 mg/kg, SC) for 42 days increased serum levels of ALT and AST, as well as the MDA content, in brain and liver tissues, but decreased the GSH content. Additionally, the levels of apoptotic proteins, including Bax, procaspase-3 and caspase-3 cleaved, were markedly increased. N. sativa oil (0.1 and 0.2 mL/kg) diminished the levels of the biochemical markers ALT and AST. Administration of black seed oil (0.1, 0.2 and 0.5 mL/kg) reduced lipid peroxidation and at doses 0.1 and 0.2 mL/kg significantly recovered the GSH content. The oil decreased Bax/Bcl2 levels and at 0.1 mL/kg down-regulated the expressions of caspase-3 (pro and cleaved) proteins in brain and liver tissues. Conclusion: Through its antioxidant and anti-apoptosis properties, black seed oil exhibited an anti-aging effect in a model of aging induced with D-galactose.

• The Journal of Advanced Prosthodontics
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• 제14권6호
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• pp.360-368
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• 2022

PURPOSE. This study assessed the physical and mechanical properties of interim crown materials fabricated using various digital techniques after accelerated aging. MATERIALS AND METHODS. Three groups of interim dental restorative materials (N = 20) were tested. The first group (CO) was fabricated using a conventional manual method. The second group (ML) was prepared from prefabricated resin blocks for the milling method and cut into specimen sizes using a cutting disc. The third group (3D) was additively manufactured using a digital light-processing (DLP) 3D printer. Aging acceleration treatments using toothbrushing and thermocycling simulators were applied to half of the specimens corresponding to three years of usage in the oral environment (N = 10). Surface roughness (Ra), Vickers microhardness, 3-point bending, sorption, and solubility tests were performed. A 2-way analysis of variance (ANOVA) and Fisher's multiple comparison test were used to compare the results among the groups. RESULTS. The mean surface roughness (Ra) of the resin after accelerated aging was significantly higher in the CO and ML groups than that before aging, but not in the 3D group. All groups showed reduced hardness after accelerated aging. The flexural strength values were highest in the 3D group, followed by the ML and CO groups after accelerated aging. Accelerated aging significantly reduced water sorption in the ML group. CONCLUSION. According to the tested material and 3D printer type, both 3D-printed and milled interim restoration resins showed higher flexural strength and modulus, and lower surface roughness than those prepared by the conventional method after accelerated aging.

• 치과방사선
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• 제13권1호
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• pp.29-73
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• 1983

The age related changes in the life cycle of the progenitor cell population of murine oral epithelia was studied. Using radioautographic methods which have been adopted in previous cell cycle studies, the age-related changes of different phases in renewing cells of the palatal, buccal and lingual mucosae were determined. The results confirm published findings on cell cycle changes of epithelia with aging and illustrated further that mitotic phase which has hither to been considered stationary, also changes with aging. The major parts revealed by this study are as follows: 1) The basal progenitor cells in different regions of oral mucosa have different generation times. 2) The basal cell cycle time increases as a function of aging and the region most affected by aging appears to be the epithelium of the cheek. 3) The phases of the cell cycle affected by the process of aging are in increasing order of magnitude: M-, S- and G₁-phase. 4) The age elated change in the number of DNA synthesizing basal progenitor cells occurs at two age periods. Between 1 and 12 months of life it decreases, while from 12 to 20 months it increases.

• 가족자원경영과 정책
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• 제14권4호
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• pp.323-340
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• 2010

Many social and environmental changes have emerged due to the increasing size of the aging generation. This study explored the current status of the information leisure activity of the aging generation (computer use activity, internet service participation, social community participation and blogging, UCC, etc.) and the need for serious games among elderly consumers. It analyzed the current status of serious game and information leisure span as determined by experts on elderly care at the aging welfare institute. The research methods involved applying content analysis and focus group interviews. The results were as follows: The elderly are willing to enjoy the internet and economics networks. In particular, economic investment, economic news, health, meetings, and communication are the main internet search categories. The results for serious games are less interesting than those for IT participation. The components of usefulness in terms of serious games, as identified by care experts, are simplicity, a user-friendly interface, efficacy, and certainty in using the game device. Care experts recognize that serious games represent a supplementary device to traditional physical and emotional therapy.

• 한국보건간호학회지
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• 제34권2호
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• pp.198-210
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• 2020

Purpose: This study was undertaken to identify the effect of current health conditions and preparation for old age of university students on the awareness of successful aging. Methods: Totally, 273 university students, based across several cities in South Korea, were enrolled for the study. Data collected were analyzed by applying descriptive statistics, independent t-test, one-way ANOVA, Pearson correlation coefficients, and hierarchical multiple regression, using the SPSS Statistics 23.0. Results: There were three types of hierarchical regression model for awareness of successful aging in university students. Its explanatory power of each model was adjusted R² of .04, 07, and .31 respectively. Major (β=.14, p=.007), health condition (β=.13, p=.028), preparation for old age (β=.52, p<.001) were significant predictors of awareness of successful aging. Conclusion: Our study results indicate that for university students, diverse interventions to promote the awareness of successful aging must focus on improving the health condition and enhancing preparation for old age.

• 대한한의진단학회지
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• 제17권2호
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• pp.122-130
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• 2013

Objectives This study investigated the relationship between exercise and health factors including vaso-aging degree, stress index, stress resistance, fatigue and activity of autonomic nerve system etc. Methods The subjects were 20,509 persons who had received health examination by Korean Medicine and submitted questionnaires about exercise history, for 8 months from March to November in 2011. The vaso-aging degree were measured by APG (Accelerated Photoplethysmograph). The stress index and resistance, fatigue and activity of autonomic nerve system were measured by HRV (Heart Rate Variability). We analyzed the relationship between exercise and various variables by chi-square test with SPSS ver. 19.0. Results Regarding the relationship between exercise and vaso-aging degree, stress index, stress resistance, fatigue and activity of autonomic nerve system, there were significant differences(p<0.05). Conculsions This study suggests that vaso-aging degree, stress index, stress resistance, fatigue and activity of autonomic nerve system are affected by exercise.

• Molecules and Cells
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• 제44권3호
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• pp.136-145
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• 2021

Senescent cells that gradually accumulate during aging are one of the leading causes of aging. While senolytics can improve aging in humans as well as mice by specifically eliminating senescent cells, the effect of the senolytics varies in different cell types, suggesting variations in senescence. Various factors can induce cellular senescence, and the rate of accumulation of senescent cells differ depending on the organ. In addition, since the heterogeneity is due to the spatiotemporal context of senescent cells, in vivo studies are needed to increase the understanding of senescent cells. Since current methods are often unable to distinguish senescent cells from other cells, efforts are being made to find markers commonly expressed in senescent cells using bulk RNA-sequencing. Moreover, single-cell RNA (scRNA) sequencing, which analyzes the transcripts of each cell, has been utilized to understand the in vivo characteristics of the rare senescent cells. Recently, transcriptomic cell atlases for each organ using this technology have been published in various species. Novel senescent cells that do not express previously established marker genes have been discovered in some organs. However, there is still insufficient information on senescent cells due to the limited throughput of the scRNA sequencing technology. Therefore, it is necessary to improve the throughput of the scRNA sequencing technology or develop a way to enrich the rare senescent cells. The in vivo senescent cell atlas that is established using rapidly developing single-cell technologies will contribute to the precise rejuvenation by specifically removing senescent cells in each tissue and individual.

• The Journal of Advanced Prosthodontics
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• 제16권1호
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• pp.48-56
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• 2024

PURPOSE. To evaluate the metameric disparities among monolithic zirconia materials with differing yttrium compositions across various lighting conditions. MATERIALS AND METHODS. Thirty-six square-shaped zirconia samples measuring 10 × 10 × 0.5 mm were prepared from monolithic zirconia materials with three different yttrium contents. A 0.2 mm thick layer of polymerized dual-polymerizable self-adhesive resin cement was created using a silicone mold with the same dimensions as the prepared zirconia specimens. To evaluate metamerism, color measurements were conducted using a spectrophotometer device on a neutral gray background in a color measurement cabinet that offers four different illumination environments. All samples underwent aging by subjecting them to 10000 thermal cycles using a thermal cycle tester. Following thermal aging, color measurements were taken once more, and the data were recorded using the CIE L^*, a^*, b^* color system. Two-way ANOVA and Post-hoc Bonferroni tests were employed to analyze the data. RESULTS. It was observed that there was no statistical difference among the color measurements made in different illumination environments of the monolithic zirconia ceramics used to evaluate metamerism (P > .05). This observation remained consistent both before and after thermal aging. After thermal aging, the color of monolithic zirconia materials exhibited a tendency towards red and yellow hues, accompanied by a decrease in brightness levels. CONCLUSION. It can be stated that different illumination conditions did not affect the metamerism of monolithic zirconia materials, but there was a color change in monolithic zirconia materials after a thermal aging period equivalent to one year.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제20권4호
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• pp.81-89
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• 2014

Purpose : An aging phenomenon was recognized as only negative aspect, which impediment a development with the decrease of a developing population and increase of social burden. Nevertheless, the problem of aging cannot be treated as a problem of individuals or social burden. Because Every mankind sometime will be the person directly involved the aging. Methods : Korea, predict to reach the aging society with over 20 percent of elderly in the whole population in 2020, should find an active political plan for responding. Because a previous discussion about the aging phenomenon focused on social welfare, the housing plan for the elderly with a consideration of the physical environment for sustaining elderly's life with happiness will be primary task. Results : This research considers housing policy, focusing on the medical service. It is because statistics, which 85 percent of elderly people suffer from chronic diseases because of physical aging signify the importance of medical service to the elderly in every-day-life. Implications : We prescribe the elderly as a population over 65. In this duration, the elderly retirees from the workplace e and spend the majority of time in their home. Thus, for the elderly, the residential space is a field of action and passageway connecting with the surroundings For the solution of physical space preparing the aging phenomenon, the combination of residential and medical function creates a new type of a lifestyle.