• BMB Reports
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• 제51권2호
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• pp.59-64
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• 2018

The airway epithelium is the first place, where a defense mechanism is initiated against environmental stimuli. Mucociliary transport (MCT), which is the defense mechanism of the airway and the role of airway epithelium as mechanical barriers are essential in innate immunity. To maintain normal physiologic function, normal oxygenation is critical for the production of energy for optimal cellular functions. Several pathologic conditions are associated with a decrease in oxygen tension in airway epithelium and chronic sinusitis is one of the airway diseases, which is associated with the hypoxic condition, a potent inflammatory stimulant. We have observed the overexpression of the hypoxia-inducible factor 1 (HIF-1), an essential factor for oxygen homeostasis, in the epithelium of sinus mucosa in sinusitis patients. In a series of previous reports, we have found hypoxia-induced mucus hyperproduction, especially by MUC5AC hyperproduction, disruption of epithelial barrier function by the production of VEGF, and down-regulation of junctional proteins such as ZO-1 and E-cadherin. Furthermore, hypoxia-induced inflammation by HMGB1 translocation into the cytoplasm results in the release of IL-8 through a ROS-dependent mechanism in upper airway epithelium. In this mini-review, we briefly introduce and summarize current progress in the pathogenesis of sinusitis related to hypoxia. The investigation of hypoxia-related pathophysiology in airway epithelium will suggest new insights on airway inflammatory diseases, such as rhinosinusitis for clinical application and drug development.

• 한국버섯학회지
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• 제12권2호
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• pp.77-81
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• 2014

Mushrooms are considered not only as food but also for source of physiologically beneficial medicines. The culinary-medicinal mushrooms may important role in the prevention of age-associated neurological dysfunctions, including Alzheimer's and Parkinson's diseases. Hericium erinaceus (H. erinaceus), is edible mushrooms, is a parasitic fungus that grows hanging off of logs and trees and well established candidate for brain and nerve health. H. erinaceus contains high amounts of antioxidants, beta-glucan, polysaccharides and a potent catalyst for brain tissue regeneration and helps to improve memory and cognitive functions. Its fruiting bodies and the fungal mycelia exhibit various pharmacological activities, including the enhancement of the immune system, antitumor, hypoglycemic and anti-aging properties. H. erinaceus stimulates the synthesis of Nerve Growth Factor (NGF) which is the primary protein nutrient responsible for enhancing and repairing neurological disorders. Especially hericenones and erinacines isolated from its fruitin body stimulate NGF, synthesis. This fungus is also utilized to regulate blood levels of glucose, triglycerides and cholesterol. H. erinaceus can be considered as useful therapeutic agents in the management and/or treatment of neurodegeneration diseases. However, this review focuses on in vitro, in vivo and clinical trials for neurodegerative disease.

• 신재생에너지
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• 제2권3호
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• pp.31-36
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• 2006

Superstrate pin amorphous silicon thin-film(a-Si:H) solar cells are prepared on $SnO_2:F$ and ZnO:Al transparent conducting oxides(TCO) in order to see the effect of TCO/p-layers on a-Si:H solar cell operation. The solar cells prepared on textured ZnO:Al have higher open circuit voltage VOC than cells prepared on $SnO_2:F$. Presence of thin microcrystalline p-type silicon layer(${\mu}c-Si:H$) between ZnO:Al and p a-SiC:H plays a major role by causing improvement in fill factor as well as $V_{OC}$ of a-Si:H solar cells prepared on ZnO:Al TCO. Without any treatment of pi interface, we could obtain high $V_{OC}$ of 994mV while keeping fill factor(72.7%) and short circuit current density $J_{SC}$ at the same level as for the cells on $SnO_2:F$ TCO. This high $V_{OC}$ value can be attributed to modification in the current transport in this region due to creation of a potential barrier.

• 여성건강간호학회지
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• 제13권2호
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• pp.98-104
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• 2007

Purpose: The purpose of this study was to explore the barriers and the enhancing factors and predictors to postpartum care performance. Methods: The Research design in this study was a cross-sectional correlational survey. Subjects were 145 women at 6 to 10 weeks post delivery at an OB & GY clinic. Data was gathered with postpartum care performance, and other related variables including emotional status during pregnancy, fatigue, health recovery status, maternal role and identity. Data was analyzed using the SPSS WIN(version 11.0) program. Results: The mean score of postpartum care performance was 3.08 of 5, it had significant differences in emotional status during pregnancy, coincidence of expected sex, health recovery status, postpartum fatigue and postpartum depression. The maternal role and health recovery status were enhancing factors of postpartum care performance. Also, the barrier factors were fatigue, depression and coincidence of expected sex. Among these factors, the present health recovery status had an predictability of 11.7%, postpartum fatigue 3.2%, and coincidence of expected sex 2.5%, for a total predictability factor of 17.4% on postpartum care performance. Conclusion: Among these related factors to postpartum care performance, present health recovery status was the most predictable factor and then postpartum fatigue, and coincidence of expected sex. We need to establish a strategy to reduce postpartum fatigue and implement nursing interventions for health related consequences in postpartum women.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2018년도 전력전자학술대회
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• pp.536-538
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• 2018

This paper introduces an enhanced interleaved (IL) PFC (Power Factor Correction) boost converter typed 650V Intelligent Power Module (IPM), which is fully optimized hybrid IGBT converter modules; Silicon (Si) IGBT and Silicon Carbide (SiC) diode, for up to 10kW HVAC (Heating, Ventilation, and Air Conditioning) systems. It utilizes newly developed $4^{th}$ Generation Field Stop (FS) trench IGBTs, $EXTREMEFAST^{TM}$ anti-paralleled diodes, SiC Junction Barrier Schottky (JBS) diodes, Bridge rectifiers, Multi-function LVIC, and Built-in thermistor provide good reliable characteristics for the entire system. This module also takes technical advantage of DBC (Direct Bonded Copper) substrate for the better thermal performance. It is shown that the Si IGBT/SiC diode hybrid IL PFC module can achieve excellent EMI performance and greatly enhance the power handling capability or switching frequency of various applications compared to the Si IGBT/Diode. This paper provides an overall description of the newly developed 650V/50A Hybrid SiC IL PFC IPM product.

• 한국광학회지
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• 제6권3호
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• pp.228-232
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• 1995

초고속 광통신을 위한 고속변조용 단일모드 반도체 레이저로서 변조 도핑된 SMQW-PBH-DFB-LD를 제작하고 변조특성을 축정 하였다. 제작된 소자의 최소 임계전류는 16.0mA, 최대 slope efficiency는 0.275mW/mA였다. 고속변조를 위한 활성층의 변조도핑으로 소자의 내부손실은 $37cm^{-1}$로 크게 주어졌으나. 이득계수의 증가에 따라 선폭확대계수는 1.8로 감소되었다. 소신호 변조 특성 측정 결과, $46mA(I_{th}+30mA)$ 에서의 공진주파수 8GHz, -3dB 차단주파수 10GHz 이상으로서 고속변조 특성이 우수한 변조도핑된 SMQW-PBH-DFB-LD를 시험 제작하였다.

• E2M - 전기 전자와 첨단 소재
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• 제10권7호
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• pp.659-667
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• 1997

The influence of SiO$_2$on the microstructure and electrical properties of zinc oxide varistor was investigated. Zn$_2$SiO$_4$third phase in the sintered body was found at grain boundaries, multiple grain junctions, and occasionally within ZnO grains. This phase acted as a grain growth inhibitor, which retard the grain growth of the ZnO matrix by impeding migration on the grain boundaries. As SiO$_2$ addition increases, average grain size decreased from 40.6${\mu}{\textrm}{m}$ to 26.9${\mu}{\textrm}{m}$ due to the pinning effect by Zn$_2$SiO$_4$ and drag effect by Si segregation at grain boundaries, the breakdown voltage consequently increased. When SiO$_2$ addition is increased, interface state density decreased, however, the barrier height increased by decrease of donor concentration, as a result, the nonlinear exponent increased and leakage current decreased. While, as SiO$_2$ addition increase, it was found that the apparent dielectric loss factor shows a tendency of decrease. Wholly, electrical properties of zinc oxide varistor can be said to be improved by SiO$_2$addition.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.158-161
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• 2006

Superstrate pin amorphous silicon thin-film (a-Si:H) solar cells are prepared on $SnO_2:F$ and ZnO:Al transparent conducting oxides (TCO) In order to see the effect of TCO/P-layers on a-Si:H solar cell operation. The solar cells prepared on textured ZnO:Al have higher open circuit voltage $V_{oc}$ than cells prepared on $SnO_2:F$. Presence of thin microcrystalline p-type silicon layer $({\mu}c-Si:H)$ between ZnO:Al and p a-SiC:H plays a major role by causing improvement in fill factor as well as $V_{oc}$, of a-Si:H solar cells prepared on ZnO:Al TCO. Without any treatment of pi interface, we could obtain high $V_{oc}$, of 994mv while keeping fill factor (72.7%) and short circuit current density $J_{sc}$ at the same level as for the cells on $SnO_2:F$ TCO. This high $V_{oc}$ value can be attributed to modification in the current transport in this region due to creation of a potential barrier.

• Bulletin of the Korean Chemical Society
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• 제4권1호
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• pp.28-36
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• 1983

We considered the tunneling effect on the rate constants calculated from transition-state theory for the H + $D_2$ and D + $H_2$ reactions. A method for evaluating the important parameter Ec (potential barrier height) was proposed. A tunnel-effect correlation factor (TECF) ${\Gamma}_{t}exp{\theta}_t$ was estimated from experimental data, and compared with the corresponding values obtained from many theoretical methods. According to our results, the tunneling effect cannot be negligible around $800^{\circ}$K where the TECF value is ca. 0.8 whereas the factor approaches to unity at T > $2400^{\circ}$K where the tunneling completely disappears. In addition to the above fact, we also found that the TECF for the D + $H_2$ reaction is greater than that of the H + $D_2$ reaction in agreement with Garrett and Truhlar's result. In contrast to our result, however, Shavitt found that the order is reversed, i.e., TECF for (D + $H_2$) is greater than that for (H + $D_2$). We discussed about the Shavitt's result.

• Journal of Nutrition and Health
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• 제27권3호
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• pp.292-303
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• 1994

The present study investigated the perceptions of food adopted by Koreans using the characteristics of taste and nutrition. Two hundred and nine Korean subjects were surveyed including University students and adults from many diverse social backgrounds. The subjects sorted pictures of foods according to two conditions, how tasty and then how nutritions they thought the foods were using the Q-method. These pictures included two sets, one for individual food items and the second depicting typical Korean meals, yielding a total of four conditions, This methodology effectively addressed any language barrier as pictures and words in both Korean and English were used. It was an effective tool for allowing the identification of perceptual structures and indicating how prevalent they were across samples. The data were factor analysed and the resulting factor scores interpreted. Meat was regarded positively in all four conditions. Individual sweet foods were preferred by younger subjects while individual traditional foods were preferred by older subjects. Traditional Korean meals were also favoured while processed meals were not. Nutritionally, proteins were more valued than carbohydrates, fibre and vitamins. Meals that contained protein and were regarded as filling and sustaining were regarded positively. The implications for nutrition education were discussed.