• Title/Summary/Keyword: 메커니즘 분석

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The Whole Extract of Enterococcus faecalis Has Suppressive Effect on the Allergic Responses in Asthmatic Mouse Model (천식 마우스 모델의 알러지 반응에서 Enterococcus faecalis 전체 추출물의 억제 효과)

  • Chang, Jeong Hyun;Yang, EunJu;Yu, Sun Nyoung;Ahn, Soon-Cheol
    • Journal of Life Science
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    • v.27 no.10
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    • pp.1168-1175
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    • 2017
  • Probiotics are usually defined as intestinal bacteria that provide healthy benefit to the host and may offer new therapeutic materials for the treatment of inflammatory diseases. Lactobacillus, Bifidobacterium and Enterococcus are known as typical probiotics. But, these bacteria have mostly a weak viability and thus decreased probiotics-mediated effects in the intestinal tract. Asthma is an inflammatory airway disease, which is characterized by the releases of inflammatory mediators including cytokine and IgE. They are mainly associated with the recruitment, activation and disregulation of specific inflammatory cells, especially mast cells, monocytes, T cells, eosinophils and neutrophils in asthma. We performed these studies as in vitro and in vivo test the human inflammatory cell lines and ovalbumin (OVA)-induced asthma mouse model. And then the inhibitory effects of Enterococcus faecalis whole extract on inflammatory responses were examined. For our examinations, the E. faecalis whole extract (Ef extract) was acquired from whole bacteria of E. faecalis using freeze/thawing after ultrasonication method. As results, OVA-mediated THP-1 cell viability was decreased by the treatment of Ef extract. In the asthmatic mouse model, Ef extract inhibited the infiltration of inflammatory cells into the inflammatory sites and blood. This whole extract may have anti-asthmatic effects associated with the regulation of IL-5 and IgE expression. It may also be a promising candidate in anti-allergic medicine for the treatment of asthma.

A Study on the Formation of Lamellar Liquid Crystalline Using Skin Mimicking Surfactant (피부모사체 계면활성제를 사용한 라멜라 액정의 생성에 관한 연구)

  • Kim, In-Young;Nam, Eun-Hee;Shin, Moon-Sam
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.3
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    • pp.484-495
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    • 2020
  • This study is a mixed surfactant (MimicLipid-MSM1000) that forms the same structure as that of the stratum corneum, sucrose distearate, polyglyceryl-2 dioleate, fermented squalane, ergosterol, 10-hydroxystearic acid, mixture consisting of was synthesized. When using 2~5 wt% of this mixed surfactant, it was possible to make an artificial skin mimetic that forms a multi-layer lamellar structure of 5~30 layers. An emulsion was prepared using this mixed surfactant, and a multi-layered lamellar phase was formed and analyzed mechanically. The appearance of this surfactant was a light brown hard wax, the hydrophilic lipophilic balance (HLB) was 12.53, the critical parameter value was 0.987, and the acid value was 0.13. Stability according to pH change was also stable in acidic (3.8), neutral (7.2) and alkaline (10.8). The particle size of the liquid crystal was found to be the most stable maltese cross lamellar crystalline droplet at 5~25mm. The size of the emulsified particles according to the change in the speed of the homo agitator is 2500 rpm (17.9mm±2.6mm), 3500rpm (12.5mm±2.1mm), 4500rpm (6.2mm±1.8mm) particles were formed. Liquid crystal forming particles were observed through a polarization microscope, and the formation structure of the liquid crystal was precisely analyzed with a scanning electron microscope (cryo-SEM). As an application field, it is expected that it will be widely applicable to the development of various prescriptions, such as various skin care cosmetics, makeup care cosmetics, and scalp protection cosmetics, by using a skin-mimicking surfactant.

Anti-aging Effects of L-Carnitine on Human Skin (L-카르니틴의 사람피부에 대한 항노화 효과)

  • Lee Bum-Chun;Choe Tae-Boo;Sim Gwan-Sub;Lee Geun-Soo;Park Sung-Min;Lee Chun-Il;Pyo Hyeong-Bae
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.3 s.47
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    • pp.393-397
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    • 2004
  • L-Carnitine $({\beta}-hydroxy-{\gamma}-trimethyl-ammoniumbutyric{\;}acid)$ is a small water-soluble molecule important in mammalian fat metabolism. It is essential for the normal oxidation of fatty acids by the mitochondria, and is involved in the trans-esterification and excretion of acyl-CoA esters. In this paper, to investigate the relationship between aging and L-carnitine, we investigated the effects of in vitro matrix-metalloproteinase (MMP) inhibition and activity and expression of UYA-induced MMPs in human skin fibroblasts. Also, we studied to develop as anti-aging cosmetics with L-carnitine. Fluorometric assays of the proteolytic activities of MMP-1 (collagenase) were performed using fluorescent collagen substrates. ELISA (enzyme linked immune sorbent assay), gelatin-substrate zymography, RT-PCR ELISA techniques were used for the effects of L-carnitine on MMP expression, activity, and MMP mRNA expression in UVA irradiated fibroblast $(5\;J/cm^2)$, respectively. In addition, we performed clinical study with L-carnitine cream. L-carnitine inhibited the activities of MMP-1 in a dose-dependent manner and the $IC_{50}$ values calculated from semi-log plots were 2.45 mM, and L-carnitine showed strong inhibition on MMP-2 (gelatinase) activity in UVA irradiated fibroblast by zymography. Also, UVA induced MMP-1, 2 expression was reduced $43\%,\;53\%$ by treated with L-carnitine at 1.25 mM, and MMP-1 mRNA expression was reduced dose-dependent manner. Therefore L-carnitine was able to significantly inhibit the MMP activity, and regulate MMP expression in protein and mRNA level. The results of clinical study showed that $1.0\%$ L-carnitine treated group reduced wrinkle significantly compared with placebo treated group (P<0.05). All these results suggest that L-carnitine may be useful as new anti-aging cosmetics for protection against UVA induced Mm expression and activity.

Inhibition of Adipocyte Differentiation through G1 Arrest by Extract of Sophora tonkinensis Gapnep in 3T3-L1 Preadipocytes (산두근 추출물의 세포주기 정지를 통한 3T3-L1 지방전구세포의 분화 억제)

  • Jeong, Hyun-Young;Hyun, Sook-Kyung;Choi, Yung-Hyun;Kim, Byung-Woo;Kwon, Hyun-Ju
    • Journal of Life Science
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    • v.21 no.9
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    • pp.1346-1353
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    • 2011
  • Sophora tonkinensis Gapnep has been used as a traditional herbal medicine in oriental regions since ancient times. In this study, the effect and mechanism of the MeOH extract of Sophora tonkinensis Gapnep (STME) on adipocite differentiation and adipogenesis in 3T3-L1 preadipocites were investigated. Treatment with STME in the concentration range of 0-200 ${\mu}g$/ml significantly inhibited the differentiation of 3T3-L1 preadipocites in a dose-dependent manner, as determined by a decrease in intracellular lipid droplets and lipid contents measured by Oil Red O staining. In association with the inhibitory effect of lipid accumulation, the expressions of the proteins concerned with adipogenesis in 3T3-L1 preadipocites were also investigated. Treatment with STME reduced the expressions of peroxisome proliferator-activated receptor ${\gamma}$ (PPAR${\gamma}$), cytidine-cytidine-adenosine-adenosine-thymine (CCAAT)/enhancer-binding proteins ${\alpha}$ and ${\beta}$ (C/EBP${\alpha}$ and C/EBP${\beta}$) and sterol regulatory element binding protein (SREBP), which are adipocyte specific markers. In flow cytometry analysis, the inhibitory effect of differentiation was caused by G1 arrest and following mitotic clonal expansion cease. Therefore, we also investigated the alteration of G1 phase arrest-related proteins. As a result, the expression of p21 protein was significantly increased, while the expressions of Cdk2, E2F-1 and phospho-Rb were reduced in a dose-dependent manner in STME treated 3T3-L1 cells. According to these results, STME might inhibit differentiation through G1 arrest in 3T3-L1 preadipocytes adipogenesis, and further studies, which are in progress, have to be completed to identify the active compounds.

Failure Behavior and Separation Criterion for Strengthened Concrete Members with Steel Plates (강판과 콘크리트 접착계면의 파괴거동 및 박리특성)

  • 오병환;조재열;차수원
    • Journal of the Korea Concrete Institute
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    • v.14 no.1
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    • pp.126-135
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    • 2002
  • Plate bonding technique has been widely used in strengthening of existing concrete structures, although it has often a serious problem of premature falure such as interface separation and rip-off. However, this premature failure problem has not been well explored yet especially in view of local failure mechanism around the interface of plate ends. The purpose of the present study is, therefore, to identify the local failure of strengthened plates and to derive a separation criterion at the interface of plates. To this end, a comprehensive experimental program has been set up. The double lap pull-out tests considering pure shear force and half beam tests considering combined flexure-shear force were performed. The main experimental parameters include plate thickness, adhesive thickness, and plate end arrangement. The strains along the longitudinal direction of steel plates have been measured and the shear stress were calculated from those measures strains. The effects of plate thickness, bonded length, and plate end treatment have been also clarified from the present test results. Nonlinear finite element analysis has been performed and compared with test results. The Interface properties are also modeled to present the separation failure behavior of strengthened members. The cracking patterns as well as maximum failure loads agree well with test data. The relation between maximum shear and normal stresses at the interface has been derived to propose a separation failure criterion of strengthened members. The present study allows more realistic analysis and design of externally strengthened flexural member with steel plates.

Development of a TBM Advance Rate Model and Its Field Application Based on Full-Scale Shield TBM Tunneling Tests in 70 MPa of Artificial Rock Mass (70 MPa급 인공암반 내 실대형 쉴드TBM 굴진실험을 통한 굴진율 모델 및 활용방안 제안)

  • Kim, Jungjoo;Kim, Kyoungyul;Ryu, Heehwan;Hwan, Jung Ju;Hong, Sungyun;Jo, Seonah;Bae, Dusan
    • KEPCO Journal on Electric Power and Energy
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    • v.6 no.3
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    • pp.305-313
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    • 2020
  • The use of cable tunnels for electric power transmission as well as their construction in difficult conditions such as in subsea terrains and large overburden areas has increased. So, in order to efficiently operate the small diameter shield TBM (Tunnel Boring Machine), the estimation of advance rate and development of a design model is necessary. However, due to limited scope of survey and face mapping, it is very difficult to match the rock mass characteristics and TBM operational data in order to achieve their mutual relationships and to develop an advance rate model. Also, the working mechanism of previously utilized linear cutting machine is slightly different than the real excavation mechanism owing to the penetration of a number of disc cutters taking place at the same time in the rock mass in conjunction with rotation of the cutterhead. So, in order to suggest the advance rate and machine design models for small diameter TBMs, an EPB (Earth Pressure Balance) shield TBM having 3.54 m diameter cutterhead was manufactured and 19 cases of full-scale tunneling tests were performed each in 87.5 ㎥ volume of artificial rock mass. The relationships between advance rate and machine data were effectively analyzed by performing the tests in homogeneous rock mass with 70 MPa uniaxial compressive strength according to the TBM operational parameters such as thrust force and RPM of cutterhead. The utilization of the recorded penetration depth and torque values in the development of models is more accurate and realistic since they were derived through real excavation mechanism. The relationships between normal force on single disc cutter and penetration depth as well as between normal force and rolling force were suggested in this study. The prediction of advance rate and design of TBM can be performed in rock mass having 70 MPa strength using these relationships. An effort was made to improve the application of the developed model by applying the FPI (Field Penetration Index) concept which can overcome the limitation of 100% RQD (Rock Quality Designation) in artificial rock mass.

A Study on Correlation between El-Nino and Winter Temperature and Precipitation in Korea (엘니뇨와 한국의 겨울 기온 및 강수량과의 상관에 관한 연구)

  • Min, Woo-Ki;Yang, Jin-Suk
    • Journal of the Korean association of regional geographers
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    • v.4 no.2
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    • pp.151-164
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    • 1998
  • I analyzed the correlation between El-Nino phenomenon and our country's temperature and precipitation laying the stress on the anomaly, and the result of this analysis is as follows: (1) The extraction of the occurrences of El-Nino at the place of sea surface around Nino.3 which was known as the sea area under observation for El-Nino reveals that there are 9 years (1969, 1970, 1973, 1977, 1987, 1992, 1995, 1998) when the temperature anomaly in January is more than 1.0 during the period of research years ($1969{\sim}1998$). (2) The tendency of change of sea surface temperature around Nino.3 and that of our country are about the same, but the anomaly of Pusan and Inchon was much greater than that of Jangki in the East Coast. (3) The anomaly of sea surface temperature around Nino.3 and that of the ground temperature showed the similar changing tendency, the temperature of our country has something to do with that of sea surface as the correlation of ground temperature with the temperature of sea surface showed 0.31. Anomaly warm winter has something to do with El-Nino because the temperature of our country was high when El-Nino phenomenon appeared. (4) As for the precipitation, we can see that it has generally increased after 1989 when the phenomenon of warm climate was intense than before that year. But as we study the change of anomaly, the precipitation has less correlation in comparison with the ground temperature. The precipitation in 1973, 1983 and 1987 which were El-Nino years was correlated with El-Nino. While the change of sea surface temperature has showed a tendency of plus(+)increase since 1990, the precipitation has showed a tendency of minus (-)decrease. Therefore it seems that the temperature of sea surface has little correlation with the amount of rainfall.

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Effect of Temperature on Growth and Related Gene Expression in Alternative Type Wheat Cultivars (양절형 밀 생장에 대한 온도의 영향과 유전자 발현 양상)

  • Heo, Ji Hye;Seong, Hye Ju;Yang, Woon Ho;Jung, Woosuk
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.64 no.4
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    • pp.384-394
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    • 2019
  • We have investigated the effects of ambient temperature on the growth of wheat in Korea. The differences in the growth phase of wheat were compared according to the temperature treatment. The productive tiller number and dry weight were decreased in a plot under a higher temperature treatment. We found that the growth of Jinpum was different from that of the alternative wheat cultivars, which were bred in Korea, at 50 days after treatment. While the Jinpum wheat grown at 17℃ showed vegetative stage growth, that grown in the 23℃ growth chamber entered the heading and flowering stage. The differences in the expression of 16 genes known to be involved in high-temperature responses were checked by using Jinpum wheat 50 days after two temperature treatments (17℃ and 23℃), which showed apparent differences in expression between the higher and lower temperatures during the growth phase. In the 23℃ treatment samples, the genes with increased expression were HSP70, HSP101, VRN2, ERF1, TAA1, YUCCA2, GolS, MYB73, and Histone H2A, while the genes with decreased expression were VRN-A1, DREB2A, HsfA3, PIF4, PhyB, HSP17.6CII, rbcL, and MYB73. YUCCA2, HSP101, ERF1, and VRN-A1 showed a significant difference in gene expression between lower- and higher-temperature conditions. Overall, combining the means of the expression of various genes involved in thermosensing, vernalization, and abiotic stresses, it is possible to conclude that different sets of genes are involved in vernalization and summer depression of wheat under long term, high ambient temperature conditions.

Improvement of Energy Density in Supercapacitor by Ion Doping Control for Energy Storage System (에너지 저장장치용 슈퍼커패시터 이온 도핑 제어를 통한 에너지 밀도 향상 연구)

  • Park, Byung-jun;Yoo, SeonMi;Yang, SeongEun;Han, SangChul;No, TaeMoo;Lee, Young Hee;Han, YoungHee
    • KEPCO Journal on Electric Power and Energy
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    • v.5 no.3
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    • pp.209-213
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    • 2019
  • Recently, demand for high energy density and long cycling stability of energy storage system has increased for application using with frequency regulation (F/R) in power grid. Supercapacitor have long lifetime and high charge and discharge rate, it is very adaptable to apply a frequency regulation in power grid. Supercapacitor can complement batteries to reduce the size and installation of batteries. Because their utilization in a system can potentially eliminate the need for short-term frequent replacement as required by batteries, hence, saving the resources invested in the upkeep of the whole system or extension of lifecycle of batteries in the long run of power grid. However, low energy density in supercapacitor is critical weakness to utilization for huge energy storage system of power grid. So, it is still far from being able to replace batteries and struggle in meeting the demand for a high energy density. But, today, LIC (Lithium Ion Capacitor) considered as an attractive structure to improve energy density much more than EDLC (Electric double layer capacitor) because LIC has high voltage range up to 3.8 V. But, many aspects of the electrochemical performance of LIC still need to be examined closely in order to apply for commercial use. In this study, in order to improve the capacitance of LIC related with energy density, we designed new method of pre-doping in anode electrode. The electrode in cathode were fabricated in dry room which has a relative humidity under 0.1% and constant electrode thickness over $100{\mu}m$ was manufactured for stable mechanical strength and anode doping. To minimize of contact resistance, fabricated electrode was conducted hot compression process from room temperature to $65^{\circ}C$. We designed various pre-doping method for LIC structure and analyzing the doping mechanism issues. Finally, we suggest new pre-doping method to improve the capacitance and electrochemical stability for LIC.

Design of accelerated life test on temperature stress of piezoelectric sensor for monitoring high-level nuclear waste repository (고준위방사성폐기물 처분장 모니터링용 피에조센서의 온도 스트레스에 관한 가속수명시험 설계)

  • Hwang, Hyun-Joong;Park, Changhee;Hong, Chang-Ho;Kim, Jin-Seop;Cho, Gye-Chun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.24 no.6
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    • pp.451-464
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    • 2022
  • The high-level nuclear waste repository is a deep geological disposal system exposed to complex environmental conditions such as high temperature, radiation, and ground-water due to handling spent nuclear fuel. Continuous exposure can lead to cracking and deterioration of the structure over time. On the other hand, the high-level nuclear waste repository requires an ultra-long life expectancy. Thus long-term structural health monitoring is essential. Various sensors such as an accelerometer, earth pressure gauge, and displacement meter can be used to monitor the health of a structure, and a piezoelectric sensor is generally used. Therefore, it is necessary to develop a highly durable sensor based on the durability assessment of the piezoelectric sensor. This study designed an accelerated life test for durability assessment and life prediction of the piezoelectric sensor. Based on the literature review, the number of accelerated stress levels for a single stress factor, and the number of samples for each level were selected. The failure mode and mechanism of the piezoelectric sensor that can occur in the environmental conditions of the high-level waste repository were analyzed. In addition, two methods were proposed to investigate the maximum harsh condition for the temperature stress factor. The reliable operating limit of the piezoelectric sensor was derived, and a reasonable accelerated stress level was set for the accelerated life test. The suggested methods contain economical and practical ideas and can be widely used in designing accelerated life tests of piezoelectric sensors.