PPG 센서 수신기용 Switched Capacitor를 활용한 Transimpedance Amplifier 회로

강상진(Sangjin Kang),김솔지(Solji Kim),김선국(Sunkook Kim),이성호(Sungho Lee) 대한전자공학회 2018 대한전자공학회 학술대회 Vol.2018 No.6

One of the main challenges for PPG (Phtoplethysmography) sensors is eliminating ambient light signal for improved signal quality. The PPG sensors are so popular in wearable applications that they should be small and low power consumption. In this paper, we propose a Transimpedance Amplifier (TIA) using Switched Capacitor (SC) technique. By adding SC, we achieve 20∼35.5dB gain signal compared to ambient light signal and 28 W low power consumption in 1.75×1.75 mm2 chip size.

아우구스티누스와 고전적 덕론(德論)의 변형

강상진(Sangjin Kang) 인제대학교 인간환경미래연구원 2010 인간 · 환경 · 미래 Vol.- No.5

서양 덕론의 역사에서 결정적인 분기점을 만들어 준 작가로 아우구스티누스를 들 수 있다. 덕을 통해, 즉 인간의 기능을 잘 수행하는 것에 따라 행복에 이른다는 고전적인 생각의 자리에 아우구스티누스는 자기 사랑과 하느님 사랑이라는 양극성에 근거한 모델을 제시한다. 아우구스티누스가 그리스도적 지복과 동일시하는 참된 행복은 덕을 통한 인간의 성공적 삶에서 성립할 수 없다. 고전적 덕은 비이성적 감정들을 지배하는데 성공할 수 있지만, 비이성적 감정 자체가 이미 사랑의 방향을 함축하고 있기 때문이다. 고전적 덕론에서 핵심적인 역할을 하는 습관화는 예기치 않았던 사랑의 관점을 만나게 되는 것이다. 덕이 올바른 사랑의 질서에 놓이지 않는 한, 감정에 대한 지배력이나 인간 행복에 대한 기여는 제한적일 수밖에 없다. 여기에 덕론의 역사에서 주목할 만한 무게 중심의 이동이 있다. 수단과 목적의 구조는 불변이지만 각각의 기능을 수행하는 것으로 이해되던 덕이 이제 사랑의 방향이 어느 쪽인가에서 성립하는 것으로 이해되기 때문이다. 이런 의미에서 아우구스티누스의 덕론은 고전적 덕론의 변형으로 이해할 수 있다. In Augustine we can find a turning point in the history of western theories of virtue. Instead of the happiness that human beings reach through virtues, i.e. through performing well their functions, Augustine posits a model based upon the polarity between the love of self and the love of God. True happiness, identified by Augustine with the Christian beatitude, cannot consist in human flourishing through virtues. Classical virtues may succeed in restraining irrational passions, but disruptive passions are themselves indicative of direction of love. The habituation, key process of classical virtues, seems to have to face an unexpected aspect of love. Unless virtues are placed under the right order of love, according to Augustine, their reigning powers over the passions and their implementation of the human happiness can have only a limited significance. We notice here a shift of the main focus in the theory of virtues, namely from the performance of the appropriate functions to the polar direction of love, even though the means-end structure left intact. In this sense we interpret the Augustinian contribution as a transformation of the classical theory of virtue.

3D 피부세포 배양계를 이용한 피부광노화 연구

강상진 ( Sangjin Kang ) 대한화장품학회 1999 대한화장품학회지 Vol.25 No.2

Skin is continuously exposed to external stimuli including ultraviolet radiation, which is a major cause of skin photoaging. According to recent discoveries, UVA with a lower energy but deep-penetrating properties, compared to UVB, is likely to play a major part in causing skin photoaging. The clinical and histochemical changes of photoaging are well characterized, but the biochemical mechanisms are poorly understood partly due to the lack of suitable experimental systems. In this work, three-dimensional, reconstituted skin culture models were prepared. After certain period of maturation, the equivalent models were shown to be similar in structure and biochemical characteristics to normal skin. Mature dermal and skin equivalent models were exposed to sub-lethal doses of UVA, and the effects of UVA relevant to dermal photoaging were monitored, including the production of elastin, collagen, collagenase(MMP-1), and tissue inhibitor of metalloproteinases-1 (TIMP-1). Interestingly, dermal and skin equivalents reacted differently to acute and chronic exposure to UVA. Elastin production was increased as soon as one week after commencing UVA irradiation by chronic exposure, although a single exposure failed to do so. This early response could be an important advantage of equivalent models in studying elastosis in photoaged skin. Collagenase activity was increased by acute UVA irradiation, but returned to control levels after repeated exposure. On the other hand, collagen biosynthesis, which was increased by a single exposure, decreased slightly during 5 weeks of prolonged UVA exposure. Collagenase has been thought to be responsible for collagen degeneration in dermal photoaging. However, according to the results obtained in this study, elevated collagenase activity is not likely to be responsible for the degeneration of collagen in dermal photoaging, while reduced production of collagen may be the main reason. It can be concluded that reconstituted skin culture models can serve as useful experimental tools for the study of skin photoaging. These culture models are relatively simple to construct, easy to handle, and are reproducible. Moreover, the changes of dermal photoaging can be observed within 1 ~ 4 weeks of exposure to ultraviolet light compared to 4 months to 2 years for human or animal studies. These models will be useful for biochemical and mechanistic studies in a large number of fields including dermatology, toxicology, and pharmacology. The aging of human skin is a complex process in which many factors contribute to the age-related changes. One of these factors relates to UV-radiation, but the exact mechanistic details are not well established. Skin is directly exposed to environmental stresses, particularly ultraviolet(UV) radiation from the sun, which induces various sorts of photodamage. The short-term exposure to UV results in inflammation, skin darkening, and decreased immune function. Beside the acute effects, repeated exposure to the sun for long periods induces deep wrinkles, loss of elasticity, and premature aging, usually referred to as “photoaging’,^1-3. Accumulating evidence suggests that alterations in the dermal extracellular matrix are primarily responsible for the clinical appearance of photodamaged skin^1,4. There is an accumulation of amorphous mass of elastotic material in the papillary dermis5, 6 with degeneration of collagen⁷ and changes in the proteoglycan contents⁸. Within sunlight, UVB is primarily responsible for most biological effects including inflammation, changes in pigmentation, immunosupression and carcinogenesis. However, UVA radiation, once believed harmless to skin, is now recognized as being capable of producing profound damage to most epidermal and dermal components^3,9. It is not only the larger amount of UVA reaching to the skin that makes UVA an important cause of photoaging, but also UVA can penetrate deep into the dermis¹⁰. Solar UVB radiation is known to induce various effects in many cases as a result of the direct absorption of photons by DNA and proteins in mammalian skin^11,12. In contrast, the skin-damaging effects of UVA appear to result from oxygen-mediated photodynamic reactions in which UVA in the presence of certain photosensitizing chromophores(e.g. riboflavin, porphyrins, NADPH etc.) leads to the formation of reactive oxygen species¹³. Because of these differences, UVA and UVB show different biological effects on the skin. The important point with respect to the present work is that the effects of UVA are closely related to the changes occurring on a result of aging process such as free radical formation13, impairment of cutaneous antioxidant defense system¹³, protein crosslinking^14,15, and age-associated changes of dermal protein metabolism, such as increased elastin and collagenase production^16,17. Thus UVA probably plays a more important role in dermal photoaging than UVB. Almost all the studies published to date about photoaging were performed in vitro using monolayer cell culture^18-21 or in vivo on animal and human skin^22-26. Both of these systems have some shortcomings. Cells in monolayer culture, in a situation far removed from that in vivo, show different behavior and respond differently to external stimuli including UV radiation. These cells show rapid proliferation and are actively producing extracellular matrix components and remodeling enzymes. Moreover, skin fibroblasts and keratinocytes can not be maintained long enough to reveal signs of aging without passage, which change may overwhelm or negative the effects of UV exposure. On the other hand, in vivo models are good for endpoint studies of the effects of long-term UV exposure. However, it is difficult to perform controlled experiments on the study of the mechanism and control of photoaging, because these systems are too complicated and it takes long time to see the initial signs of photoaging^22,23. Since reconstituted three-dimensional cultures of skin were developed^27,28, many improvements have been made for equivalent models to produce structure and function similar to those in in vivo state^29,30. In this study, dermal and skin equivalent models were prepared and subjected to repeated exposure to sublethal doses of UVA radiation, to see if these models are suitable for the investigation of dermal photoaging. Dermal equivalents, consisted of normal human skin fibroblasts and type I collagen isolated from rat tail, showed extensive contraction, which ceased at about two weeks after fabrication. During this period, fibroblasts underwent striking morphological changes ; the cells which were stellate in the early stages lost their dendrites and assumed a bipolar morphology(Fig. la, b). Parallel with the contraction, which is believed to be similar to what happens in the wound healing process, the production of elastin, one of the extracellular matrix components, was enhanced and returned to its normal level followed by a transient increase in the level of remodeling enzyme(collagenase) activity (Fig. 2). These results indicate that an initial maturation period was required during which fibroblasts remodel the extracellular matrix and regain their normal physiological state. The rapid proliferation of fibroblasts which occurring during the initial stages also decreased and, after this maturation period, the number of fibroblasts remained approximately constant. To prepare skin equivalent, normal human keratinocytes were seeded on top of the dermal equivalent. About 48 hours after seeding onto derma】 equivalents the keratinocytes were confluent, and the cultures were then raised to the air/liquid interface. Stratum corneum and suprabasal layers were apparent as early as 3 days after air/liquid exposure, which became mature, with 10-15 suprabasal layers and thick stratum corneum, within 3 weeks. The deposition of basement membrane components, type IV collagen and laminin, were visualized by immunohistochemistry. The patches of type IV collagen were recognized one week after air/liquid exposure, and continuous deposition of type IV collagen and laminin were observed at three weeks. In this study, fibroblasts in dermal and skin equivalents, after certain period of maturation, showed relatively normal metabolic features of the dermal extracellular components and have produced a good basement membrane. Therefore, the effects of extrinsic stimuli on 'normal5 cells may be studied in these models, which are simple and in which it is easy to control the experimental conditions compared to the more complex in vivo model systems. To evaluate the effects of single exposure to UVA radiation, monolayer culture of fibroblasts and mature dermal and skin equivalents were exposed to varying doses of UVA(0 to 40 J/ cm²). At least 95% of fibroblasts in dermal equivalents were viable following exposure to 5 J/cm² UVA. Interestingly, as seen in normal human skin, sunburn cells could be observed in skin equivalents, 24 hours after irradiation with 40 J/cm² UVA. Elastin biosynthesis was measured in the conditioned media of cultures irradiated with varying doses of single UVA irradiation (0 to 30 J/cm²). There was no difference in elastin levels/unit cell number in the conditioned media from fibroblasts both in monolayer cultures and in dermal equivalents. Acute UVA seems to have little or no effect on elastin biosynthesis in fibroblasts in monolayer culture and in equivalent models. [³H]-proline incorporation into collagenous protein by fibroblasts in dermal equivalents was increased 3-fold by as little as 5 J/cm² UVA irradiation, and no further increase was observed by higher UVA dosages(Fig. 3■). On the other hand, collagen biosynthesis in sham-irradiated monolayer cultures was similar to that of irradiated dermal equivalents and the level was decreased dose-dependently by UVA irradiation(Fig. 3◆). Collagenolytic activities in conditioned media from dermal and skin equivalent cultures were assayed after UVA irradiation. Little activity was detected in the medium without APMA treatment, indicating that most of the MMP-1 is present in latent form. Although the total activities were not significantly changed by UVA irradiation, the activity per unit cell number showed dose-dependent increase(Fig. 4). The mRNA levels of MMP-1 were dramatically elevated both in dermal and skin equivalents with higher levels in skin equivalents, while TIMP-1 gene expression showed slight increase(Table 1). To evaluate the effects of chronic UV exposure, Dermal and skin equivalents were exposed to sublethal doses of UVA(5 J/cm²) five days a week for up to 5 weeks. Strikingly, dermal and skin equivalent models responded differently to acute and chronic exposure to UVA light. In contrast to the acute effect, elastin concentrations released into the conditioned media from both dermal and skin equivalents were increased by repeated exposure to UVA irradiation within a week and increased further until 3 weeks(Fig. 5a). Similar elevation patterns were observed in both dermal and skin equivalents. The initial elevated levels of collagen synthesis in UVA-irradiated dermal and skin equivalents returned to those of non-irradiated controls within one week, and a slow reduction in collagen biosynthesis was observed showing about 20% reduction after 5 weeks of repeated exposure. This effect was similar in both dermal and skin equivalents except that a higher collagen biosynthesis was observed in skin equivalents(Fig. 5b). Collagenase activities in both dermal and skin equivalent models were increased during the early period of UVA exposure. However, after prolonged exposure, these elevated collagenase activities returned to normal. In dermal equivalents, collagenase activity showed a peak at 5 days after the start of irradiation and returned to the level of non-irradiated controls after 2 weeks(Fig. 6■). The similar but slower response was seen in skin equivalents, showing collagenase activities peaking after 1 ~ 2 weeks and returning to normal after 4 weeks of irradiation (Fig. 6▲). Higher collagenase activities in non-irradiated control were noticed in skin equivalents than dermal equivalents. Also, the return of elevated collagenase activities to normal levels took a longer time in skin equivalents than dermal equivalents. Elevated collagenolytic activity following UV exposure in fibroblasts in monolayer culture as well as in human or animal skin have repeatedly been reported by several groups, suggesting that the reduced collagen content in photoaged skin is a result of increased or accelerated degradation. Most of these data were obtained by single or several exposure to relatively large amount of UV radiation. However, because aging is generally considered as a result of accumulation of minor damage over a long period, it is worth confirming whether the same result is obtained following longterm exposure to low levels UV radiation or whether the damage is produced by different or additional mechanisms. In the study reported here, reconstituted skin cultures were repeatedly irradiated with sublethal doses of UVA and the changes in collagen biosynthesis and collagenolytic activity were monitored. Acute and chronic UVA exposure brought about different results in dermal metabolism in equivalent models. Elastin production was enhanced only after repeated exposure to UVA. Increased collagen biosynthesis was observed after single exposure, but the opposite was seen following repeated exposure. Also, collagenase activity, which was enhanced by a single UVA irradiation, returned to normal after several weeks of chronic UVA exposure. The mechanisms leading to these different responses are not known. Possible explanations could include feedback control by the extracellular concentration and activity of the proteins and enzymes or their degradation products, or a different set of signals triggered by repeated UV exposure leading to different results. Overall one can conclude that the biochemical modifications that follow repeated exposure to UVA are not the result of simple accumulation of the effects brought about by single exposure and therefore it is not appropriate to explain the changes in photoaged skin on the basis of data obtained in experiments in which there is single or short-term UV exposure. For example, the enhanced collagenolytic activities were thought to be responsible for the decreased collagen levels in photoaged skin based on results obtained from acute exposure to ultraviolet in in vivo and in vitro experiments^17,32,33 in contrast, according to the results from the present study, however, decreased collagen biosynthesis might be a more important reason for this change and may help to resolve the confusion originating from different results obtained under varying experimental conditions and in different models. The early signs of skin photoaging, such as increased elastin production and reduced collagen synthesis, could be recognized in equivalent models within a relatively short period compared to in vivo models. These changes could explain the mechanism of solar elastosis and degeneration of collagen in photoaged skin, and agreed well with other Tesults, such as reduced type I and III procollagen levels in photoaged human skin compared with the light-protected skin of the same patients³⁴, elevated elastin and fibrillin gene expression in photoaged skin²⁴, and enhanced elastin promotor activities in transgenic mice³⁵. The different basal levels of collagen and collagenase, and the different responsiveness to chronic UVA in collagenase activities, between dermal and skin equivalents might reflect the role of keratinocytes and epidermal cytokines in producing dermal changes after UVA exposure. The results in this study suggest that reconstituted skin culture model is a useful tool for the study of photoaging. There are some limitations, however, with present techniques skin equivalent models can only be maintained for relatively short periods, say a maximum of 7 to 8 weeks after exposure at the air/liquid interface, and thereafter lose their structure and viability for the reasons that are not clear. More importantly, these models do not contain other types of ceils which are known to play significant roles in UV-induced skin responses, including skin-residing Langerhans5 cells, melanocytes, macrophages, and neutrophils^25,36. Especially cells from blood vessels secret cytokines as well as various matrix-degrading enzymes, such as collagenase, gelatinase, and elastase, in response to the inflammatory signals including UV radiation^37,38. Neutrophil- derived lysozyme and elastase may also participate in producing elastosis^39,40.

한국어 쓰기 평가 점수의 공정성 연구 - 평가 방법, 평가자 요인, 학습자 요인의 영향에 대한 교차분류 다층분석 -

정지윤 ( Chong Jiyun ),강현화 ( Kang Hyounhwa ),강상진 ( Kang Sangjin ) 한국문법교육학회 2018 문법 교육 Vol.33 No.-

The purpose of this study is to investigate how the scores of Korean language tests are influenced by the characteristics of examines, raters, and scoring methods. Data consist of 240 scores from the 24 raters who evaluated five students’ essays in two scoring methods, that are analytical and holistic methods. We focused on the effect of scoring methods and the rater severity along with their language differences and years of teaching experiences. For the analysis, we employed the Cross-classified Multilevel Models(CMM) in order to estimate the effects of scoring methods, of rater severity, of native language and of the teaching experiences simultaneously. We found the holistic scoring method was much more generous than analytical approach, and there existed very strong effects of rater severity. Other variables showed little effects on the test scores.

사람 섬유아세포에서 세리신잠 실샘가수분해물(Sericinjam Gland Hydrolysate)의 항산화 및 항노화 효과

천유리 ( Yuri Cheon ),황정욱 ( Jung Wook Hwang ),이희삼 ( Heui Sam Lee ),윤세영 ( Seiyoung Yun ),최용수 ( Yong-soo Choi ),강상진 ( Sangjin Kang ) 대한화장품학회 2013 대한화장품학회지 Vol.39 No.1

본 논문에서는 세리신잠 실샘 가수분해물(Sericinjam Gland Hydrolysate: SJGH)을 이용하여 진피 섬유아세포에서 항산화 및 항노화 연구를 진행하였다. SJGH는 사람 섬유아세포에서 고농도의 과산화수소에 의한 세포사멸과 세포 내 산화 증가를 효과적으로 방어하였다. 또한 SJGH는 저농도의 과산화수소에 의한 섬유아세포의 SA-β-Gal 발현과 MMP-1의 발현 증가를 억제하였고, 반대로 프로콜라겐 I의 생합성은 증가시켰다. 이러한 결과를 통해 SJGH의 항산화 및 항노화 효과가 우수함을 확인하였으며, SJGH가 항노화 화장품의 우수한 소재가 될 수 있음을 보여준다. We studied the anti-oxidant and anti-aging activities of Sericinjam Gland Hydrolysate (SJGH) in the human dermal fibroblasts. SJGH effectively defended cell death and ROS generation under high H₂O₂ in human dermal fibroblasts. Moreover SJGH reduced the expression of SA-β-Gal and MMP-1 under low concentration of H₂O₂ whereas biosynthesis of procollagen-Ⅰ was increased. This results demonstrate the anti-oxidant and anti-aging activities of SJGH. SJGH could be a good candidate for anti-aging cosmetics ingredient.

사람 모유두세포에서 코르티코트로핀분비인자에 의한 모발성장관련사이토카인의 발현 조절

이은영 ( Eun Young Lee ),전지혜 ( Ji Hye Jeon ),이민호 ( Min Ho Lee ),이승호 ( Sunghou Lee ),김영호 ( Young Ho Kim ),강상진 ( Sangjin Kang ) 대한화장품학회 2014 대한화장품학회지 Vol.40 No.4

코르티코트로핀분비인자(Corticotropin-releasing factor)는 스트레스 반응에 관여하는 호르몬으로, 최근 스트레스가 탈모와 같은 피부질환에 영향을 미친다는 보고들이 많아지고 있다. 보고에 따르면, 사람 모낭 배양에서 코르티코트로핀분비인자는 길이생장을 억제하며, 모낭의 조기퇴행을 유도하고 모기질각질형성세포(hair matrix keratinocyte)의 세포사멸을 촉진시킨다. 본 연구에서는 코르티코트로핀분비인자가 모발성장과 모주기 조절에 핵심적으로 역할하는 모유두세포에 미치는 영향에 대해 알아보고자 했다. 시상하부-뇌하수체-부신축의 주요 스트레스호르몬들인 코르티코트로핀분비인자, 부신피질자극호르몬, 그리고 코르티솔을 사람 모유두세포에 처리하였다. 흥미롭게도, 코르티코트로핀분비인자가 모발성장과 관련된 사이토카인(KGF, Wnt5a, TGFβ-2, Nexin)의 발현을 변화시키는 것을 관찰하였으며, 세포 내 cAMP의 수준을 증가시켰고, 수용체의 발현을 억제시켰다. 이러한 변화는 수용체의 길항제인 antalarmin과 astressin2B, 또는 PKA 억제제의 전처리로 인해 막을 수 있었다. 코르티코트로핀분비인자는 cAMP/PKA경로를 통해 POMC의 발현을 유도하는데, 사람 모유두세포에서도 이 호르몬의 처리가 POMC mRNA의 발현을 증가시키는 것을 확인할 수 있었으나 부신피질자극호르몬의 변화는 western blot으로는 확인할 수 없었다. 이러한 결과들을 바탕으로, 코르티코트로핀분비인자가 그 수용체를 통해 사람 모유두세포 내 모발성장 관련 사이토카인의 발현을 조절함을 확인하였으며, 이는 코르티코트 로핀분비인자의 수용체 길항제가 스트레스성 탈모환자를 위한 치료제 혹은 화장품 소재로써 활용될 수 있음을 보여준다. Corticotropin-releasing factor (CRF) is involved in the stress response and there is increasing evidence that stress influences skin disease such as hair loss. In cultured human hair follicles, CRF inhibits hair shaft elongation, induces premature regression and promotes the apoptosis of hair matrix keratinocytes. We investigated whether CRF influences the dermal papilla cells (DPC) that play pivotal roles in hair growth and cycling. Human DPCs were treated with CRF, adrenocorticotropic hormone (ACTH) and cortisol, key stress hormones along the hypothalamic-pituitary -adrenal (HPA) axis for 1-24 h. Interestingly, CRF modulated the expression of cytokines related to hair growth (KGF, Wnt5a, TGFβ-2, Nexin) and increased cAMP production in cultured DPCs. CRF receptors were down-regulated by negative feedback systems. Pretreatment of CRF receptor antagonists or protein kinase A (PKA) inhibitor prevented the CRF-induced modulation. Since the CRF induces proopiomelanocortin (POMC) expression through the cAMP/PKA pathway, we analyzed POMC mRNA. CRF stimulated POMC expression in cultured human DPCs, yet we were unable to detect ACTH levels by western blot. These results indicate that CRF operates within DPCs through CRF receptors along the classical CRF signaling pathway and CRF receptor antagonists could serve as potential therapeutic and cosmetic agents for stress-induced hair loss.

Angelica^®의 피부 광노화에 대한 효과

진무현 ( Mu Hyun Jin ),정민환 ( Min-hwan Jung ),임영희 ( Young-hee Lim ),이상화 ( Sang Hwa Lee ),강상진 ( Sangjin Kang ),조완구 ( Wan-goo Cho ) 대한화장품학회 2005 대한화장품학회지 Vol.31 No.3

피부노화는 피부의 이상현상이나 질환은 아니며 나이가 들어감에 따라 시간의 진행에 따라 일어나는 퇴행성 변화로 외적형태의 변화로는 피부 건조 및 주름 등이 있다. 주름을 생성하는 원인에는 자외선, 건조 및 물리적, 화학적 자극 등 환경요인에 기인하는 피부 스트레스와 각질층의 수분량 저하, 비후화, 진피의 교원섬유, 탄력섬유의 양적, 질적 변화 등이 유발하는 피부의 탄력성이나 신축성의 저하를 들 수 있다. 본 연구에서는 Angelim dahurica root에서 얻어진 3종의 주름개선 유효성분의 구조분석 및 피부 노화에 대한 효과를 살펴보았다. Skin aging is not a disease nor an abnormal phenomenon but a collection of degenerative changes with age, characterized by skin dryness, wrinkle formation, and loss of skin elasticity. The skin wrinkles are caused by either genetically predisposed factors or environmental factors such as UV irradiation or physical/chemical stimulus. The histological manifestations of wrinkles are changes in both amount and integrity of elastic and collagen fibers. Here we report the isolation and characterization of 3 active compounds, prangenidin, 8-hydroxybergapten, and xanthotoxol from Angelica dahurica root. The anti-wrinkle activities of these compounds were also investigated.

Brown Guinea Pig와 Hairless Mouse를 이용한 광노화 모델에서 LGNC-5의 경구반복투여에 의한 피부주름발생 및 색소침착억제 효과

노경옥(Kyong-Ok No),조호성(Ho-Song Cho),박상기(Sang-Ki Park),이헌식(Heon-Sik Lee),장민열(Min-Youl Chang),이민호(Min-Ho Lee),강상진(Sangjin Kang),조완구(Wan-Goo Cho),박혜지(Hye Ji Park),홍진태(Jin Tae Hong) 한국실험동물학회 2004 Laboratory Animal Research Vol.20 No.4

비타민과 불포화지방산, 그리고 폴리페놀의 복합처방인 LGNC-5 (LG생활건강 기술연구원 개발)가 건강기능식품의 개별인증을 받을 수 있는지의 여부를 확인하기 위해 hairless mice와 brown guinea pig 모델을 이용해 자외선에 의한 주름생성 및 색소침착 억제력 평가를 실시하여 다음과 같은 결괴를 얻었다. 1. Hairless mice를 대상으로 실시한 주름억제실험에서 육안관찰과 피부주형의 영상분석결과, LGNC-5군은 농도의존적인 주름발생 억제효과를 보였으며, 고용량군(x60)인 LGNC-5H군의 경우 10주후 정상군과 유사한 수준의 양호한 피부 상태를 보였다. Hematoxylin & Eosin stain 에서도 LGNC-5H군에서는 UV 대조군에 비해 표피 두께와 과각화가 현저하게 줄어드는 것으로 조사되어 우수한 주름발생억제 효과를 확인하였다. 2. Brown guinea pig을 대상으로 실시한 색소침착억제력 실험에서 육안관찰과 색차계를 이용한 측정결과, LGNC-5H군에서는 설험개시 7일 후부터 UV 대조군에 비해 색소침착이 억제되기 시작해, 설험 종료시까지 색소침착억제효과를 보였다(p<0.05). Fontana-masson silver stain 에서도 LGNC-5H군에서는 UV 대조군에 비해 melanin 침챡량이 현저하게 감소된 것으로 조사되어 LGNC-5H의 색소침착억제효과를 확인하였다. 3. 10주간의 주름억제실험과 4주간의 색소침착 억제실험에 사용한 모든 설험동물에서 사망 혹은 시험물질 투여로 인한 특이한 임상증상이 관찰되지 않았다. 시험물질 투여 기간 중 사료와 음수 소비량 역시 유의한 변화를 관찰할 수 없었으며, 대조군과 실험군 모두 정상적인 체중 증가를 나타내었다. 이상의 실험결과를 종합하면 LGNC-5은 안전하고 경구반복투여 시 UV조사로 인해 hairless mice에서 발생되는 주름과 brown guinea pig에서 생성되는 색소침착을 효과적으로 억제시키는 처방인 것으로 평가되었다. Chronic exposure of UV radiation in sunlight results in a number of biological responses, including erythema, sunburn cell formation, immune suppression, photoaging, and skin cancer. In this study, we investigated the effects of LGNC-5 (LG Nutricosmetics-5, the mixture of vitamins, unsaturated fatty acid and polyphenol) on UV-induced skin damage. Oral administration of LGNC-5 for 10 weeks resulted in inhibition of UVB-induced wrinkle formation in SKH-1 hairless mice skin compared to UV control group as a dose dependent manner. LGNC-5 treatment also inhibited UV radiation-induced skin pigmentation in brown guinea pigs examined by colorimeter and Fontana-masson silver staining. These results mean that LGNC-5 as a dietary supplement could be useful to attenuate solar UVB-induced melanogenesis and premature skin aging.

기업의 사회적 책임에 따른 퇴직급여제도와 기업위험

망갈바자르바토구(Mangalbazar Battogoo),반혜정(Ban, Hye-Jung) 한국경영교육학회 2020 경영교육연구 Vol.35 No.6

[연구목적] 본 연구는 CSR이 우수한 기업일수록 종업원의 복리후생을 위하여 확정급여형 퇴직급여제도를 운영하며 이로 인하여 기업 위험이 감소하는지 분석하고자 한다. 확정급여제도 하에서는 퇴직급여에 대한 위험을 기업이 부담하게 되지만 CSR이 우수한 기업의 경우 확정급여제도를 통하여 근로자의 퇴직연금 수급권을 안정화시키고자 할 것으로 기대하기 때문이다. 그리고 이러한 관련성이 대리인 비용에 따라 차이를 보이는지 검증한다. [연구방법] 2014년부터 2018년까지 유가증권시장 상장법인을 표본으로 실증분석을 수행한다. CSR과 퇴직급여제도 및 기업 위험 간의 관련성을 검증하기 위하여 기업의 퇴직급여제도는 연구모형 내 매개변수로 작용하며 Baron and Kenny(1986)의 3단계 분석을 실시하여 가설을 검증한다. [연구결과] 대리인 비용이 낮은 기업의 경우 종업원 퇴직 이후의 재무적 위험 공유에 대한 책임 있는 활동을 통하여 시장에서 긍정적으로 평가받을 수 있다는 증거를 발견하였다. 그러나 사외적립자산 규모가 증가할수록 기업의 현금흐름 변동성은 증가할 수 있는 것으로 나타났다. [연구의 시사점] 본 연구는 기업이 사회적 문제에 관심을 가지고 보다 장기적인 관점에서 종업원 퇴직 이후의 재정적 위험을 공유하는지에 관한 증거를 도출하고 선행연구에 공헌할 것으로 기대한다. 그리고 기업의 대리인 문제가 낮을수록 CSR의 긍정적인 효과가 증가하는지 분석함으로써 사회공동체와 윤리적 가치가 일치하는 순수한 CSR이 기업의 위험을 완화시킬 수 있다는 함의를 제공할 것으로 기대한다. [Purpose] This study examines whether the defined benefit plan according to CSR contributed financially to household income after retirement and that it reduces coporate risk. And we verify to analyze whether this relevance is different according to the agency problem. [Methodology] An empirical analysis is conducted using a sample of corporations listed on the securities market from 2014 to 2018. According to the research design to verify the relationship between CSR and retirement benefit plans and corporate risk, we conduct a three-step analysis of Baron and Kenny (1986). [Findings] We found evidence that companies with low agency costs can reduce market risk through responsible activities for sharing financial risks after retirement of employees according CSR and positively evaluated in the market. However, as the size of plan assets increases, the volatility of corporate cash flows can increase. [Implications] This study provides implications that high CSR companies make responsible decisions for employees by sharing financial risks after retirement. It is expected to provide implications that pure CSR can mitigate corporate risk as the agency problem of a company decreases.

보에티우스, 『철학의 위안』 5권 4장의 기술 논변에 대한 검토

강상진 ( Kang¸ Sang-jin ) 한국가톨릭철학회 2019 가톨릭철학 Vol.0 No.33

보에티우스 『철학의 위안』 5권에서 논의되는 신의 예지와 인간의 자유의지 사이의 양립가능성 문제에 대한 첫 번째 응답은 기술적 영역에 속하는 사안을 중심으로 구성된다. 이 논문은 지금까지 주목받지 못한 이 기술 논변이 구체적으로 어떤 통찰을 전해주고 있는지, 또 이어지는 전체 논증에서 어떤 역할을 하고 있는지 분석한다. 기술적 영역은 특정한 조건이 주어지면 기술의 투입을 통해 의도했던 효과가 발생하기에 충분할 정도의 구조를 갖추고 있다는 점에서 필연성에 대한 앎을 허락하지만, 이 필연성이 인간적 판단과 의지라는 조건에 의존하는 만큼 반드시 그런 결과가 나와야만 할 필연성은 없는 영역이다. 보에티우스는 이 모델을 토대로 미래 결과에 대한 앎은 성립하지만, 그 앎이 미래 사건이 자유롭지 않게 만드는 필연성을 부여하는 것은 아니라는 점을 보여준다. 기술 논변은 짧은 논증 속에서 자신에게 기대되는 역할을 성공적으로 수행한 것으로 평가할 수 있다. The response to the problem of compatibility between divine foreknowledge and human free will in Boethius’ Consolation of Philosophy, Book 5, starts with the examples from the craftsmanship. This article tries to answer the question, what insights this short argument provides, and which role it plays in the subsequent and whole argumentation. The realm of craftsmanship permits us the knowledge of future effects on the basis of mechanism put by the craftsmanship itself. However, this knowledge of future effects depends on the will and judgment of human beings to use the craftsmanship. Boethius’s argument from the craftsmanship shows a prima facie compatibility between the foreknowledge and the not-compelled event. Although his argument doesn’t solve all the problems, we can evaluate it as successful.