• Journal of Aerospace System Engineering
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• v.18 no.4
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• pp.70-80
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• 2024

In this study, we explore the purpose, origin, and history of thermal testing in the development of artificial satellite components. We seek to understand precisely the test variables associated with thermal vacuum and thermal cycle tests, including temperature margins and cycle counts, which may differ according to the development model. We analyze specifications detailed in standards from NASA, ESA, MIL, and others. Furthermore, given the recent surge in interest in CubeSats and nanosatellites, this paper aims to identify research trends in customizing satellite development projects according to their budget and duration.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.4
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• pp.321-330
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• 2014

Ultraviolet B (UVB) is a primary environmental factor that induces adverse effects on skin such as photoaging, skin burn and cancer. UVB also increases the expression of $11{\beta}$-hydroxysteroid dehydrogenase type 1 ($11{\beta}-HSD1$), which converts inactive cortisone to active cortisol in response to a variety of stressors in target tissues. Thus, we have screened new herbal extracts that suppress $11{\beta}-HSD1$ expression induced by UVB in human dermal fibroblasts. We also investigated whether Trapa japonica (TJ) extract and its fractions inhibit UVB-induced photoaging in Hs68 cells and 3D skin model. Results showed that TJ extract inhibited the increase of $11{\beta}-HSD1$ expression in UVB-exposed Hs68 cells significantly. TJ extract and its fractions not only inhibited $11{\beta}-HSD1$ expression, but also suppressed the increase of matrix metalloproteinases (MMP-1, 3, 9) and proinflammatory cytokines (IL-6, 8) in UVB-irritated Hs68 cells. TJ extract also inhibited MMP-1 expression in UVB-irritated 3D skin model. In addition, TJ extract recovered UVB-induced decreases of epidermal thickness and PCNA-positive cells in 3D skin model. Taken together, these results suggest that TJ extract and its fractions inhibit UVB-induced skin photoaging by interfering with $11{\beta}-HSD1$ and MMPs.