• Title/Summary/Keyword: Mechanistic study

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Cadmium induces apoptosis in human lung fibroblast by inducing oxidative stress: A role of Bax and Bcl-2

  • Oh, Seon-Hee;Lee, Guang-Yong;Lee, Mi-Ock;Moon, Chang-Kiu;Lee, Byung-Hoon
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.106.1-106.1
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    • 2003
  • Cadmium (Cd) is an inorganic toxicant of great environmental and occupational concern which was classified as a human carcinogen in 1993. Occupational cadmium exposure is associated with lung cancer in human. In the present study, we established the mechanistic basis of apoptotic cell death induced by Cd in WI38 human lung fibroblast. Cd at 20-80 ${\mu}$M decreased viablility of cells in a concentration-dependent manner. PI staining, TUNEL staining and DNA fragmentation analysis demonstrated the apoptotic cell death by Cd. (omitted)

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Flow regime transition criteria for vertical downward two-phase flow in rectangular channel

  • Chalgeri, Vikrant Siddharudh;Jeong, Ji Hwan
    • Nuclear Engineering and Technology
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    • 제54권2호
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    • pp.546-553
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    • 2022
  • Narrow rectangular channels are employed in nuclear research reactors that use plate-type nuclear fuels, high heat-flux compact heat exchangers, and high-performance micro-electronics cooling systems. Two-phase flow in narrow rectangular channels is important, and it needs to be better understood because it is considerably different than that in round tubes. In this study, mechanistic models were developed for the flow regime transition criteria for various flow regimes in co-current air-water two-phase flow for vertical downward flow inside a narrow rectangular channel. The newly developed criteria were compared to a flow regime map of downward air-water two-phase flow inside a narrow rectangular channel with a 2.35-mm gap width under ambient temperature and pressure conditions. Overall, the proposed model showed good agreement with the experimental data.

"동의보감(東醫寶鑑)" "내경편(內景篇)"의 포(胞), 소변(小便), 대편(大便)에 나타난 질병(疾病)의 변증화(辨證化) 연구 (Study on Mechanistic Pattern Identification of Disease for Uterine, Urine and Excrements Parts of DongEuiBoGam NaeGyungPyen)

  • 김영목
    • 동의생리병리학회지
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    • 제24권5호
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    • pp.727-736
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    • 2010
  • This study is about researching mechanistic pattern identification of disease for DongEuiBoGam NaeGyungPyen by analysing with pattern identification of modern Traditional Korean medical patholgy as more logical, systematic and standardized theory. Disease pattern mechanisms of uterine, urine and excrements parts of DongEuiBoGam NaeGyun gPyen in NaeGyungPyen of DongEuiBoGam are these. Menstrual irregularities in DongEuiBoGam can be classified flui d-humor depletion, blood deficiency, qi deficiency, qi stagnation, qi stagnation complicated by heat, blood stasis, blood deficiency complicated by heat, syndrome of heat entering blood chamber, syndrome of cold entering blood chamber. The disease pattern of abdominal pain after menstruation in DongEuiBoGam is blood deficiency complicated by heat, and a dysmenorrhea represents blood stasis with heat, fluid-humor deficiency. Advanced menstruation represent dual heat of the qi and blood, delayed menstruation is blood deficiency. The disease pattern of inhibited urination in DongEuiBoGam can be classified deficiency heat pattern of kidney yin deficiency(yin deficiency with effulgent fire), kidney qi deficiency, yin deficiency with yang hyperactivity, fluid-humor depletion, spleen-stomach dual deficiency, and excess he at pattern of bladder excess heat. The disease pattern of urinary incontinence in DongEuiBoGam can be classified deficiency pattern of kidney-bladder qi deficiency, consumptive disease, lung qi deficiency, kidney yin deficiency(yin deficiency with effulgent fire), kidney yang deficiency and excess pattern of lower energizer blood amassment, bladder excess heat. And most of them are deficiency from deficiency-excess Pattern Identification. The disease pattern of diarrhea in DongEuiBoGam can be classified deficiency pattern of qi deficiency, qi fall, spleen yang deficiency, kidney yang deficiency and so on and excess pattern of wind-cold-summerheat-dampness-fire, phlegm-fluid retention, dietary irregularities, qi movement stagnation. And most of them are deficiency from deficiency-excess Pattern Identification. Like these, this study identify pattern of disease in DongEuiBoGam by mechanism of disease theory.

Lysophosphatidic Acid-Induced TWIST1 and Slug Expression in Oral Cancer Cell Invasion

  • Cho, Kyung Hwa
    • 치위생과학회지
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    • 제17권5호
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    • pp.433-438
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    • 2017
  • Relative to its incidence, oral cancer has serious negative social effects. The exact causes of oral cancer have not been clarified, but many studies have implicated smoking and drinking. However, the fundamental mechanism of oral cancer causation has yet to be elucidated. Lysophosphatidic acid (LPA) augments epithelial mesenchymal transition (EMT) and development of various cancer cells. However, a detailed mechanistic explanation for LPA-induced EMT and the effects of EMT-promoting conditions on oral squamous cell carcinoma development remain elusive. In the present study, a quantitative reverse transcription polymerase chain reaction was used to analyze TWIST1, Slug, E-cadherin, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) transcript expression. Immunoblotting was used to analyze TWIST1, Slug, E-cadherin, and GAPDH protein expression. siRNAs were used to silence TWIST1 and Slug transcript expression. A matrigel-coated in vitro invasion insert was used to analyze oral cancer cell invasion. The results of the present study show that the expression levels of TWIST1 and Slug, which are EMT factors, were increased by LPA treatment in YD-10B oral squamous cell carcinoma. Conversely, E-cadherin expression was significantly reduced. In addition, transfection of the cells with TWIST1 and Slug siRNA strongly inhibited LPA-induced oral cancer cell invasion. The present study shows that TWIST1 and Slug mediate LPA-induced oral cancer cell EMT and invasiveness. The present study confirmed the mechanism by which LPA promotes oral cancer cell development, with TWIST1 and Slug providing novel biomarkers and promising therapeutic targets for oral cancer cell development.

프랙탈 기하학을 활용한 현대건축의 유기적 표현특성에 관한 연구 (A Study on the Characteristics of Organic Expression in Contemporary Architecture with Fractal Geometry)

  • 노정하;이근택;홍현진
    • 대한건축학회논문집:계획계
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    • 제35권4호
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    • pp.25-36
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    • 2019
  • Contemporary architecture is showing its deconstruction and departure from modern architecture based on rationality, such as reductionism or virtualism. This means a shift from a mechanistic and ecological world view to an organic and ecological view, from a deterministic reason to a reason for a possible secret static. This study examines the potential of fractals, a scientific theory of complexity that is emerging as a new paradigm in the 21st century, as an appropriate alternative to contemporary complexity architecture. The method and scope of this study were understood and its features were identified through literature and data research and prior study review. Based on the organic nature of fractal geometry, we analyzed the works of contemporary architects(Frank Gehry, Bernard Tschumi, Steven Holl, Zaha Hadid, Rem Koolhaas, Daniel Libeskind, Zvi Hecker, Ito Toyo) and studied the possibility of architectural design using the principle of fractal. As a result, fractal geometry, similar to the patterned order of nature, has an infinite set of organizational functionalities in architecture and can be applied in various aspects of design analysis. Architectural designs based on the fractal theory will require more research and development to realize dynamic design representation using digital computers.

프랜차이즈 본사의 외부환경이 경영성과에 미치는 영향 -앙트러프러너십, 시장지향성, 및 조직구조의 매개변수를 중심으로- (Effects of External Environment of Franchisor on Corporate Performance -Focused on Entrepreneurship, Market Orientation and Organizational Structure-)

  • 이태용;유영진
    • 한국콘텐츠학회논문지
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    • 제11권3호
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    • pp.351-367
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    • 2011
  • 선행연구들은 외식 프랜차이즈 환경에서 프랜차이저의 앙트러프러너 활동에 관한 프랜차이지의 지각을 거의 취급하고 있지 않고 있다. 따라서 본 연구는 프랜차이지의 관점에서 프랜차이저의 외부환경, 앙트러프러너 전략, 기계-유기 조직, 및 경영성과와의 관계를 공변량구조분석을 통하여 분석하였다. 자료는 2009년 10월1일부터 2010년 2월 28일까지 전국의 외식 프랜차이지를 605명을 대상으로 설문조사를 수집하였다. 분석 결과에 의하면 외부환경은 앙트러프러너 전략에 정(+)의 영향을 주고, 앙트러프러너 전략은 다시 시장 지향성과 경영성과에 정(+)의 영향을 미치는 것으로 나타났다. 이와 동시에 시장지향성은 유기적 조직을 채택하도록 만들었으며, 경영성과를 제고하는 것으로 나타났다. 또한 외부환경은 유기적 조직을 채택하도록 유도하였으며, 경영성과를 악화시킨 것으로 나타났다. 본 연구의 시사점은 첫째, 프랜차이저가 적극성, 혁신성, 및 위험추구성을 어느 정도 가지고 있느냐에 따라서 프랜차이즈 조직은 만족할 만한 경영성과와 현대 기업들이 필수적으로 갖추어야 될 시장지향성을 보유하게 되며, 둘째, 프랜차이저들은 시장지향성을 구성하고 있는 고객지향성, 경쟁지향성, 부서간 조화, 장기성, 수익성을 염두에 두면서 시장점유율을 유지 및 성장시켜야 하고, 셋째, 외식환경이 최근 상당히 역동적으로 그리고 비우호적으로 변화하는 관계로 이것이 조직 구조를 개편하게 만들고, 또한 경영성과에 나쁜 영향을 미치고 있는 만큼 외부환경에 대한 긴밀한 탐사가 필요하다고 하겠다.

Forecasting of Various Air Pollutant Parameters in Bangalore Using Naïve Bayesian

  • Shivkumar M;Sudhindra K R;Pranesha T S;Chate D M;Beig G
    • International Journal of Computer Science & Network Security
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    • 제24권3호
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    • pp.196-200
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    • 2024
  • Weather forecasting is considered to be of utmost important among various important sectors such as flood management and hydro-electricity generation. Although there are various numerical methods for weather forecasting but majority of them are reported to be Mechanistic computationally demanding due to their complexities. Therefore, it is necessary to develop and build models for accurately predicting the weather conditions which are faster as well as efficient in comparison to the prevalent meteorological models. The study has been undertaken to forecast various atmospheric parameters in the city of Bangalore using Naïve Bayes algorithms. The individual parameters analyzed in the study consisted of wind speed (WS), wind direction (WD), relative humidity (RH), solar radiation (SR), black carbon (BC), radiative forcing (RF), air temperature (AT), bar pressure (BP), PM10 and PM2.5 of the Bangalore city collected from Air Quality Monitoring Station for a period of 5 years from January 2015 to May 2019. The study concluded that Naive Bayes is an easy and efficient classifier that is centered on Bayes theorem, is quite efficient in forecasting the various air pollution parameters of the city of Bangalore.

Acid-Catalyzed Hydrolysis of Hexacyanoferrate (III) to Prussian Blue via Sequential Mechanism

  • Youngjin Jeon
    • 대한화학회지
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    • 제68권3호
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    • pp.139-145
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    • 2024
  • This study aims to elucidate the mechanism involved in the hydrolysis of the hexacyanoferrate(III) complex ion (Fe(CN)63-) and the mechanism leading to the formation of Prussian blue (FeIII4[FeII(CN)6]3·xH2O, PB) in acidic aqueous solutions at moderately elevated temperatures. Hydrolysis constitutes a crucial step in generating PB through the widely used single-source or precursor method. Recent PB syntheses predominantly rely on the single-source method, where hexacyanoferrate(II/III) is the exclusive reactant, as opposed to the co-precipitation method employing bare metal ions and hexacyanometalate ions. Despite the widespread adoption of the single-source method, mechanistic exploration remains largely unexplored and speculative. Utilizing UV-vis spectrophotometry, negative-ion mode liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), and a devised reaction, this study identifies crucial intermediates, including aqueous Fe2+/3+ ions and hydrocyanic acid (HCN) in the solution. These two intermediates eventually combine to form thermodynamically stable PB. The findings presented in this research significantly contribute to understanding the fundamental mechanism underlying the acid-catalyzed hydrolysis of the hexacyanoferrate(III) complex ion and the subsequent formation of PB, as proposed in the sequential mechanism introduced herein. This finding might contribute to the cost-effective synthesis of PB by incorporating diverse metal ions and potassium cyanide.

Leukemia Stem Cells in Blood Cells; Focused on Acute Myeloid Leukemia

  • Lee, Ji Yoon
    • 대한의생명과학회지
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    • 제23권1호
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    • pp.1-7
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    • 2017
  • It is known that acute myeloid leukemia (AML) is a heterogeneous blood cancer, which is enormously propagated by self-renewing leukemia stem cells (LSCs). The persistence of LSCs after chemotherapy can contribute to minimal residual disease and relapse by LSCs can be evoked promptly. Elucidating special molecules and cellular activity of LSCs is an extremely important to eliminate AML. Despite an increasing understanding of the origin of LSCs by incessant study, AML still remains a notorious disease with high mortality. An exact identification of the LSCs that sustain the proliferation of neoplastic clone is a fundamental issue in AML treatment. CD34+CD38- conventional phenotype is overall regarded as LSCs, but it has a limitation that is still hard to demarcate exactly due to similarity with normal hematopoietic stem cells (HSCs). Not all primary blasts and progenitors have equal function, thus a bona fide marker for identifying LSCs from HSCs is needed in hematologic malignancy, especially in AML. These findings have direct important implications in both in mechanistic study of LSCs as well as in the strategies of more effective therapies. In this review, I briefly summarized current advances in LSCs biology, focusing on membrane markers and a functional behavior of LSCs in AML treatment with monoclonal antibodies. Ultimately, it may be helpful in overviewing the status of LSC research, while expecting the clinic benefits of target therapy by specific inhibition.

교차로 포장 소성변형 저감을 위한 해석적 연구 (An Analytical Study to Reduce Plastic Deformation in Intersection Pavements)

  • 최준성;이강훈;권수안;정진훈
    • 한국도로학회논문집
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    • 제14권4호
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    • pp.29-36
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    • 2012
  • PURPOSES : Plastic deformation is frequently made in intersection asphalt pavement at its early age due to deceleration and stoppage of vehicles. This study has been performed to provide a mechanistic basis for reasonable selection of paving method to minimize the plastic deformation at intersection. METHODS : Pavement layer, temperature, traffic volume of the intersections managed by the Daejeon Regional Construction and Management Administration were collected to calculate asphalt dynamic modulus with pavement depth by using a prediction equation suggested by the Korean pavement design guide. Performance of ordinary dense-graded asphalt pavement, polymer modified asphalt pavement, and fiber reinforced asphalt pavement was analyzed by finite element method and the results were used in a performance model to predict the plastic deformation. RESULTS : In aspect of performance, the three paving methods were usable under low traffic while the fiber reinforced asphalt pavement was the most suitable under heavy traffic. CONCLUSIONS : Reasonable paving method suitable for traffic characteristics in the intersection might be decided by considering economic feasibility.