• 한국염색가공학회지
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• 제13권6호
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• pp.77-77
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• 2001

This study investigates the rheological properties of in-situ polymerized solutions of polyacrylonitrile(PAN) and acrylonitrile(AN)-itaconic acid(IA) in dimethyl sulfoxide(DMSO) in terms of temperature, concentration, and time. The complex viscosity and storage modulus of the solutions were generally increased with elapsing time, which is ascribable to the three-dimensional pseudostructures formed by strong inter- or intra-molecular attractions through Polar -CN and -COOH groups. The three-dimensional pseudonetworks would lead to gelation of the acrylic solutions in long term. This was more noticeable at higher temperature within the temperature range examined. In the case of 20% solutions one can not observe lower Newtonian flow region in the viscosity curve. Disappearance of lower Newtonian flow region is indicative of heterogeneity of the solution system. Casson Plot of the viscosity data revealed that 20% solutions of PAN and AN-IA copolymer in DMSO clearly demonstrated positive yield stress, ascertaining formation of pseudostructures in the solution systems.

• BMB Reports
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• 제52권10호
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• pp.589-594
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• 2019

Single-molecule techniques have been used successfully to visualize real-time enzymatic activities, revealing transient complex properties and heterogeneity of various biological events. Especially, conventional force spectroscopy including optical tweezers and magnetic tweezers has been widely used to monitor change in DNA length by enzymes with high spatiotemporal resolutions of ~nanometers and ~milliseconds. However, DNA metabolism results from coordination of a number of components during the processes, requiring efficient monitoring of a complex of proteins catalyzing DNA substrates. In this min-review, we will introduce a simple and multiplexed single-molecule assay to detect DNA substrates catalyzed by enzymes with high-throughput data collection. We conclude with a perspective of possible directions that enhance capability of the assay to reveal complex biological events with higher resolution.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.1901-1906
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• 2012

Background: The discovery that microRNA (miRNA) regulates metastasis provide a principal molecular basis for tumor heterogeneity. A characteristic of solid tumors is their heterogenous distribution of blood vessels, with significant hypoxia occurring in regions (centers of tumor) of low blood flow. It is necessary to discover the mechanism of breast cancer metastasis in relation to the fact that there is a differential distribution of crucial microRNA in tumors from centers to edges. Methods: Breast tissues from 48 patients (32 patients with breast cancer) were classified into the high invasive and metastatic group (HIMG), low invasive and metastatic group (LIMG), and normal group. Samples were collected from both the centers and edges of all tumors. The first six specimens were detected by microRNA array, and the second ten specimens were detected by real-time qRT-PCR and Western blot analyses. Correlation analysis was performed between the miRNAs and target proteins. Results: The relative content of miR-20a and miR-20b was lower in the center of the tumor than at the edge in the LIMG, lower at the edge of the tumor than in the center in the HIMG, and lower in breast cancer tissues than in normal tissues. VEGF-A and HIF-1alpha mRNA levels were higher in the HIMG than in the LIMG, and levels were higher in both groups than in the normal group; there was no difference in mRNA levels between the edge and center of the tumor. VEGF-A and HIF-1alpha protein levels were higher in the HIMG than in the LIMG, and protein levels in both groups were higher than in the normal group; there was a significant difference in protein expression between the edge and center of the tumor. Correlation analysis showed that the key miRNAs (miR-20a and miR-20b) negatively correlated with the target proteins (VEGF-A and HIF-1alpha). Conclusions: Our data suggest that miR-20a and miR-20b are differentially distributed in breast cancer, while VEGF-A and HIF-1alpha mRNA had coincident distributions, and VEGF-A and HIF-1alpha proteins had uneven and opposing distributions to the miRNAs. It appears that one of the most important facets underlying metastatic heterogeneity is the differential distribution of miR-20a and miR-20b and their regulation of target proteins.

• 한국지하수토양환경학회지:지하수토양환경
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• 제11권5호
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• pp.1-8
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• 2006

본 연구에서는 매립장에서 하부 지반으로 누출된 침출수의 이동에 흡착 불균질성이 미치는 영향을 평가하고자 하였다. 이를 위하여 차수막이 설치되어 있지 않은 매립장을 대상으로 일련의 Monte-Carlo 시뮬레이션을 수행하고 그 결과를 검토하였다. 균질한 지층에서 강불균질 지층에 이르는 다양한 불균질도를 가진 랜덤 분배계수 장에 대하여 포화 유동 모델과 오염물 이동 모델을 연결시켜 침출수의 이동을 계산하였다. 100회에 걸쳐 수행된 Monte-Carlo 시뮬레이션의 결과치로부터 얻은 평균, 표준편차, 변이계수와 같은 점기반 통계치들을 이용하여 화학적 불균질도의 영향을 평가하였다. 통계치 결과에 따르면 매립지반의 분배계수 분포가 지반 내 침출수 농도를 결정하는데 매우 중요한 인자로 나타났다. 균질 흡착의 경우와 비교할 때 불균질 분배계수 장에서는 실현 간 침출수 농도 분포의 변동성이 나타났다. 분배계수 장의 분산 및 오염원과 감시정 간의 이동 시간이 커질수록 농도의 변동성이 증가하였다. 이러한 결과는 화학적 변동성이 큰 지반 내에서의 침출수 이동을 예측할 때 단일 분배계수 값을 사용하면 상당한 오차를 유발할 수 있음을 나타낸다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권3호
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• pp.111-122
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• 2014

Partitioning interwell tracer test (PITT) is a method to quantify and qualify a site contaminated with NAPLs (Non-Aqueous Phase Liquids). Analytical description of PITT assumes that the injection-pumping well pair is on the line of the ambient groundwater flow direction, but the test-well pair could frequently be off the line in a real field site, which could be an erroneous factor in analyzing PITT data. The purpose of this work is to study the influence of the angle of the test-well pair on the ambient groundwater flow direction based on the result from PITT. From the experiments, it was found that the obliqueness of the test-well pair to the ambient groundwater flow direction could affect the tracer test resulting in a decreased NAPL estimation efficiency. In case of an oblique arrangement of the test-well pair to the ambient flow direction, it was found that the injection of a chase fluid could enhance the estimation efficiency. An increase of the pumping rate could enhance the recovery rate but it cannot be said that a high pumping rate can increase the test efficiency because a high pumping rate cannot give partitioning tracers enough time to partition into NAPLs. The results have a implication that because the arrangement of the test-well pair is a controlling factor in performing and interpreting PITT in the field in addition to the known factors such as heterogeneity and the source zone architecture, flow direction should be seriously considered in arranging test-well pair.

• Geomechanics and Engineering
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• 제13권4호
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• pp.671-683
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• 2017

Groundwater control is a significant issue in most underground construction. An estimate of the inflow rate is required to size the pumping system, and treatment plant facilities for construction planning and cost assessment. An estimate of the excavation-induced drawdown of the initial groundwater level is required to evaluate potential environmental impacts. Analytical and empirical methods used in current engineering practice do not adequately account for the effect of the jointed-rock-mass anisotropy and heterogeneity. The impact of geostructural anisotropy of fractured rocks on tunnel inflows is addressed and the limitations of analytical solutions assuming isotropic hydraulic conductivity are discussed. In this paper the unexcavated Zagros tunnel route has been classified from groundwater flow point of view based on the combination of observed water inflow and numerical modeling results. Results show that, in this hard rock tunnel, flow usually concentrates in some areas, and much of the tunnel is dry. So the remaining unexcavated Zagros tunnel route has been categorized into three categories including high Risk, moderately risk and low risk. Results show that around 60 m of tunnel (3%) length can conduit the large amount of water into tunnel and categorized into high risk zone and about 45% of tunnel route has moderately risk. The reason is that, in this tunnel, most of the water flows in rock fractures and fractures typically occur in a clustered pattern rather than in a regular or random pattern.

• International Journal of Industrial Entomology and Biomaterials
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• 제35권1호
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• pp.39-44
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• 2017

The venome of Phoneutria nigriventer spider has been shown to have side effects including severe painful erections that last for hours. PnTx2-6, a toxin from P. nigriventer spider venom, modulates voltage gated $Na^+$ channels and activation of nitric oxide (NO) production. NO is essential for the regulation of blood flow and pressure. Therefore, PnTx2-6 is expected to be effective not only for erectile dysfunction but also for cardiovascular diseases. A previously has reported cDNA clone for PnTx2-6 toxin, which was expressed in E. coli cytoplasm. We created the same clone and expressed it in a bacterial expression system. PnTx2-6 increased the genes expression of superoxide dismutase 1, glutathione peroxidase 1, and sulfiredoxin 1. We hypothesized that recombinant PnTx2-6 may indirectly regulate blood flow and pressure, resulting in NO production in human umbilical vein endothelial cells (HUVEC). These data suggest differential regulation of the vascular ageing process, which may contribute to the anatomic heterogeneity of atherosclerosis. The results of this study may be used for the emergency treatment of sudden cardiovascular disease caused by ageing.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.212-212
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• 2015

So far, geomorphologic dispersion due to the heterogeneity characteristics of flow paths in a basin has been demonstrated as a major factor affecting to the hydrologic response function of a catchment. This effect has considered by many previous studies taking into account flow path length factors, especially in the application of width function. Based upon the analysis of topographic index, another important geomorphologic factor extracted from DEM data, this work presents a new factor named saturation to evaluate its effects to the formation of the well-known instantaneous unit hydrograph (IUH) in Nash model and drainage structure in a river basin. First, the geomorphologic parameters corresponding to different saturation conditions are computed from DEM data with the support of GIS software. Then, in the combination of hydrologic and geomorphologic data, effective rainfall in each saturation degree and the Nash parameters are calculated using excel. Finally, the verification process with direct runoff data is conducted using Fortran programming. This process is applied to five sub-watersheds in Bocheong catchment ($485.21km^2$) in Korea where the necessary data are available and believable. The results from this approach will improve researchers and students'understandings about the relationship between rainfall and runoff and its relation with drainage structure within a catchment.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권4호
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• pp.12-22
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• 2014

This study evaluated the pattern of groundwater fluctuation in cyrstalline rock using time series and factor analyses. From the results, groundwater level for the 18 wells was classified into 4 types reflecting the hydrogeological properties and rainfall event. Type 1 (DB1-5, DB1-6, DB2-2, KB-10, KB-13) was significantly influenced by groundwater flow through water-conducting features, whereas type 2 (DB1-3, DB1-7, KB-1~KB-3, KB-7, KB-11, KB-14, KB-15) was affected by minor fracture network as well as rainfall event. Type 3 (DB1-1, DB1-2) was mainly influenced by surface infiltration of rainfall event. Type 4 (DB1-8, KB-9) was reflected by the irregular variation of groundwater level caused by anisotropy and heterogeneity of crystalline rock.

• 대한건축학회논문집:계획계
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• 제35권3호
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• pp.21-30
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• 2019

The purpose of this study is to investigate how Pritzker Architecture Prize as a social act has maintained an organic relationship with the architecture, the urban society through the speakings and writings of the laureates of the Pritzker Architecture Prize. The composition of this research is to grasp the background of the establishment of Pritzker Architecture Prize and the examination process, to examine its social meaning, and to identify the main flow of words from writings about the laureates through the literature survey and text frequency analysis. And is to interpret the meaning of urban society change and words about the laureates. As a result of the analysis of the flow, it is a tendency to move from ideology and style to newness and innovation, and now to publicity and sociality. Especially in recent years, a wide range of values are floated as much as the complicated issues of urban society and the natural environment. The various architectural activities that make up the urban life became more important than the building units existing like an icon. It is considered possible because the Pritzker Architecture Prize has been awarded for a sustainable common social act. In addition, through literature surveys, have also seen changes in the value of individual laureates, the mixing of styles, and the eclectic aspect. Therefore, the task of reading change should not be a process of finding a new style for a new age, but a task of acknowledging heterogeneity of each architect and recognizing diversity through pluralization.