• 대한화장품학회지
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• 제34권1호
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• pp.1-8
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• 2008

피부장벽을 포함한 표피층은 인체의 조직 가운데에서도 가장 역동적인 기관이다. 다시 말해서 끊임없이 새로운 표피세포의 형성, 분화 및 탈각과정이 반복되면서 표피항상성(epidermal homeostasis)을 유지한다. 표피항상성은 피부기능 가운데 가장 주요한 기능인 permeability barrier homeostasis의 확립으로 연결된다. Permeability barrier homeostasis는 각질층에서 이루어지며 이를 형성하고 유지하기 위해 매우 정교하게 조절되어야 한다. 표피항상성을 조절하는 핵심 조절인자로서 nuclear hormone receptor(NHR)가 중심에 있음이 최근 다양한 연구를 통해 입증되었다. 이들은 각질세포 특이적인 단백질, 즉, involucrin, loricrin 및 trans-glutaminase 1(TG 1) 등의 발현을 유전자 수준에서 조절할 뿐 아니라 표피 지질성분의 생합성을 증가시키는 등 피부장벽을 구성하는 brick 및 mortar의 생성과 유지에 핵심적 역할을 하는 것으로 알려졌다. NHR 가운데 peroxisome proliferator activator receptor(PPAR)와 liver X receptor(LXR)의 activator/ligands가 리놀레인산 등 지방산, leukotriene, prostanoid 및 oxygenated sterol 등이 지질대사과정에서 형성된 지질 종류인 까닭에 liposensor로도 알려지고 있다. 따라서 liposensor들을 비롯한 PPAR과 LXR activator/ligands들은 피부장벽기능이 저해된 아토피성 피부를 포함하여 건조피부를 관리하는 epidermotherapy의 수단으로서 잠재적 가능성이 있다고 생각된다.

• 한국구조물진단유지관리공학회 논문집
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• 제25권1호
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• pp.93-102
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• 2021

본 논문은 방현기능을 갖는 SB4등급 중앙분리대용 콘크리트 방호울타리를 개발하는 과정을 설명한다. 개발 단면은 높이와 하면의 폭이 각각 1,270mm와 560mm이다. 단면 중앙에는 방호성능을 향상하기 위해 와이어 매쉬가 배치된다. 충돌해석은 이 단면이 강도 및 탑승자 보호 성능을 만족하며 울타리에 손상이 발생하지 않는 것으로 예측하였다. 실물 충돌시험에서도 이 단면은 강도 및 탑승자 보호 성능을 만족하는 것을 확인하였다. 그러나 트럭 충돌 시 콘크리트 방호울타리 2곳에 손상이 관찰되었다. 향후 콘크리트 중앙분리대용 방호 울타리 충돌해석의 정확성을 높이기 위해서는 국내 시판 차량에 대한 모델 개발과 지속적인 충돌해석 기법에 관한 연구가 수행되어야 할 것으로 판단된다.

• 환경영향평가
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• 제17권4호
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• pp.213-224
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• 2008

Since 1970's rapid urbanization and economic growth, the population was highly increased and residential type was changed from single detached house to high density and high-rise apartment. Recently more high-rise residential building generates more traffic volumes and it makes spatial concentration. The highly traffic volumed road and high residential building was constructed nearby, it occurs noise problem. The purpose of this study is comparing the performance of three type noise barrier between noise source and receiver using a noise map simulation. Three types were composed as road side planting trees, building side planting trees and noise barrier wall. Planting trees is less effective than noise barrier wall as a noise barrier. And they are all effective under 3 stories than over 5 stories, especially noise barrier function can't work over 5 stories.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.910-912
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• 2006

Barrier ribs in plasma display panels (PDPs) function to maintain the discharge space between the glass plates as well as to prevent optical cross-talking. The barrier ribs currently employed are typically $300{\mu}m$ pitch, $110{\sim}120{\mu}m$ in height, with upper and lower widths of $50{\mu}m$ and $80{\mu}m$, respectively. It has been reported that barrier ribs can be fabricated by screen-printing, sand blasting, etching and photolithographic processes. In this study, photosensitive barrier rib pastes were formulated and systematically evaluated in terms of photolithographic process variables such as printing, drying, UV exposure, development and sintering. It was found that the use of UV absorbent, polymerization inhibitor and surfactant were very effective in controlling the width uniformity of barrier ribs in the photolithographic method of barrier rib patterning.

• 전자공학회논문지A
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• 제30A권7호
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• pp.47-59
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• 1993

16M DRAM 용 Al/Si contact 의 열적안정성을 개선하기 위하여 "stuffed" TiN/Ti diffusion barrier를 사용하였다. Diffusion barrier 로서의 특성을 개선하기 위한 Al 증착전 TiN/Ti barrier metal의 열처리 과정중 barrier metal의 두께, 열처리온도, 분위기 등을 변화시켰다. 질소분위기하에서 450도에서 TiN(900A)/Ti(300A) 박막을 열처리 하여 "stuffed" barrier metal을 형성 시켰을 경우 Al 원자의 TiN층으로의 확산의 600도에서 후속열처리한 경우 일어났으나, 700도까지도 Al-spike를 관찰할 수 없었다. 그러나 "stuffed" barrier metal을 550도에서 형성한 경우에는 600도의 후속열처리온도에서 Al이 Si 기판으로 침투했음을 관찰하였다. 박막의 두께를 얇게한 경우, 600도의 후속 열처리에서 Al-spike가 형성되었음을 확인하였다.

• 대한한의학회지
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• 제30권1호
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• pp.83-94
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• 2009

Background and Objectives: The skin barrier protects skin against a harmful environment. Its function includes an antimicrobial barrier as well as a physical barrier. Stress is harmful to the skin barrier and there are many studies on this, but there are few about the effect of stress during pregnancy on the skin barrier of offspring. The aim of this study was to investigate the effect of stress during pregnancy on the skin barrier of offspring by examination with the naked eye, cortisol, weight, TEWL and histologic tests. Materials and Methods: Male hairless mice ten weeks old were coupled with females for three days. After twelve days the females were divided into two groups. We stressed one group and not the other group. The offspring from the non-stressed (N group) and stressed (S group) grew up until four weeks. The S group was exposed to chronic mild stress using the chronic stress model protocol modified method of Wilner and Towell for a week. We made examinations with the naked eye, assessment of cortisol, weight, TEWL, and histologic test to contrast the S group with the N group. Statistical analysis was performed by using Mann-Whitney and Friedman test. Statistical significance was achieved if the probability was less than 5% (p<0.05). Results: 1. By making an examination with the naked eye, S group showed papules, creases and dryness on their skin, but N showed no change compared with normal skin. 2. There was no statistically significant difference between S group and N group in cortisol (p>0.05). 3. There was no statistically significant difference between S group and N group in weight. N group had less weight than S group (p<0.05). 4. There was no statistically significant difference between S group and N group in TEWL (p>0.05). 5. There was no statistically significant difference between S group and N group in TEWL recovery (p>0.05). 6. In TEWL and TEWL recovery, there was statistically significant difference by time between S group and N group (p<0.005). Histologically, S group showed a thicker epidermis and epidermal crest than N group. Conclusions: We found that stress during pregnancy has negative effects on the skin barrier of offspring. Though there were no statistically significant differences between S group and N group in TEWL recovery, we found evidence that the recovery of skin barrier function is interrupted by stress during pregnancy by examination with both the naked eye and histology.

• 대한화장품학회지
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• 제46권4호
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• pp.361-369
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• 2020

아토피성 피부염은 피부장벽 기능장애, 염증 및 만성 소양증을 특징으로 하는 다인성의 염증성 피부질환이다. 아토피성 피부염은 유전적, 면역학적, 환경적 요인 등의 복합적인 요인으로 피부장벽 기능과 면역기능의 장애를 유발한다고 알려져 있다. 고삼 추출물은 중국전통의학에서 사용되고 있으나, 이의 항아토피 효능에 대한 연구는 거의 진행되지 않았다. 본 연구에서는 아토피성 피부염의 주요 증상인 피부장벽 기능과 면역이상 개선에 대한 고삼추출물의 효과를 평가하였다. 고삼추출물은 피부장벽 기능에서 중요한 역할을 하는 각질세포막의 형성을 강화하는 결과를 나타내었다. 또한 피부의 보습작용에 있어서 중요한 히알루론산의 발현을 증가시키는 결과를 나타내었다. 아토피성 피부염 병변에서 특이적으로 증가하는 황색포도상구균에 대한 고삼추출물의 효능도 확인하였으며, 고삼추출물이 황색포도상구균으로부터 유도된 전염증성사이토카인의 생성을 억제함을 확인하였다. 또한 피부 스트레스 등으로 부터 생성되는 신경전달 물질인 substance P에 의해 유도된 전염증성사이토카인의 발현도 억제하는 것을 확인하였다. 이러한 결과들은 고삼추출물이 피부장벽기능과 면역반응 개선을 통해 아토피 피부염 치료에 사용될 수 있는 잠재적 후보물질임을 제시한다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.295-295
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• 2016

Recently, TCO films with low carrier concentration, high mobility and high work function are proposed beneficial as front electrode in HIT solar cell due to free-carrier absorption in NIR wavelength region and low Schottky barrier height in the front TCO/a-Si:H(p) interface. We report high transmittance and work function zirconium-doped indium tin oxide (ITO:Zr) films with various plasma (Ar/O2 and Ar) conditions. The role of (Ar/O2) plasma was to enhance the work function of the ITO:Zr films whereas the pure Ar plasma based ITO:Zr showed good electrical properties. The RF magnetron sputtered ITO:Zr films with low resistivity and high transmittance were employed as front electrode in HIT solar cells, yield the best performance of 18.15% with an open-circuit voltage of 710 eV and current density of 34.63 mA/cm2. The high work function ITO:Zr films can be used to modify the front barrier height of HIT solar cell.

• Archives of Pharmacal Research
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• 제9권3호
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• pp.119-125
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• 1986

Digitonin is a strong hemolysin and glycyrrhizin has protective activity against the deterring effect of other hemolytic saponins. The interaction of these saponins with liposomes was studied as a function of cholesterol in membrane. In the case of multilamellar vesicles, which act as ideal osmometers, digitonin distrupted the barrier function of liposomes composed of phosphatidyl choline, dicetyl phosphate and cholesterol, however, did not influence on cholesterol-lacking liposomes. Glycyrrhizin had similar effect on liposomes irrespective of cholesterol in membrane. In the test with large unilamellar vesicles, digitonin increased the lysis with increasing cholesterol content in membrane, but glycyrrhizin showed no detectable change in cholesterol-containing liposomes. These results suggest that incorporation of cholesterol into liposomes increases the susceptibility to digitonin, resulting in lysis of liposomes, and that the inhibitory effect of glycyrrhizin against other hemolytic saponins in cholesterol-independent.

• ETRI Journal
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• 제22권3호
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• pp.19-26
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• 2000

We describe a detailed numerical scheme to calculate electron transport in quantum wires using the Green function formalism combined with tight-binding orbital basis. As an example of the application, we study the electron transport in a Si nanowire containing a finite potential barrier. The effects of nonzero bias, temperature, and disorder on the barrier-induced oscillatory conductance are investigated within the context of coherent transport model. The oscillatory behavior of the conductance as a function of the Fermi energy is found to be highly sensitive to sample disorder and limited to a very low temperature and a small bias range.