• Molecules and Cells
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• v.41 no.6
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• pp.553-561
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• 2018

Icariside II (ICA II) is used in erectile dysfunction treatment. Adipose tissue-derived stem cells (ADSCs) are efficient at improving erectile function. This study aimed to explore the action mechanism of ADSCs in improving erectile function. ADSCs were isolated from the adipose tissues of rats. Cell proliferation was determined using the Cell Counting Kit-8 (CCK-8) assay. The expressions of mRNA and protein were determined separately through qRT-PCR and western blot. The endogenous expressions of related genes were regulated using recombinant plasmids and cell transfection. A Dual-Luciferase Reporter Assay was performed to determine the interaction between miR-34a and STAT3. Rat models with bilateral cavernous nerve injuries (BCNIs) were used to assess erectile function through the detection of mean arterial pressure (MAP) and intracavernosal pressure (ICP). ICA II promoted ADSCs' proliferation and differentiation to Schwann cells (SCs) through the inhibition of miR-34a. Suppressed miR-34a promoted the differentiation of ADSCs to SCs by upregulating STAT3. ICA II promoted the differentiation of ADSCs to SCs through the miR-34a/STAT3 pathway. The combination of ICA II and ADSCs preserved the erectile function of the BCNI model rats. ADSCs treated with ICA II markedly preserved the erectile function of the BCNI model rats, which was reversed through miR-34a overexpression. ICA II promotes the differentiation of ADSCs to SCs through the miR34a/STAT3 pathway, contributing to erectile function preservation after the occurrence of a cavernous nerve injury.

• Journal of Hydrogen and New Energy
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• v.20 no.3
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• pp.179-187
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• 2009

This paper presents a static and dynamic characteristics of the relief valve which is a kind of direct operated pressure control valve for hydrogen compressor. The valve is consisted of a main poppet, a spring, an adjuster and a valve body. The purpose of this study is development of the simulation model for relief valve by using commercial AMESlM$^{(R)}$ tool. Poppet with sharp edge seat type and ball poppet with sharp edge seat type compare for P-Q characteristic. The dynamic simulation results are presented the operating pressure characteristics of relief valve. High pressure power unit of which maximum pressure control range is 100MPa was manufactured, and the pressure control valve was experimented using the above-mentioned power unit. The new model of pressure control valve from this results was suggested. It was confirmed that the suggested valve has a good control performance from experimental setup.

• Journal of Integrative Natural Science
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• v.8 no.4
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• pp.273-284
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• 2015

Chemoattractant Receptor Homologous molecule expressed on Th2 cells (CRTh2) is a chemoattractant receptor with seven transmembrane helices targeted for inflammatory diseases such as asthma and allergic rhinitis. In this study, pharmacophore based Comparative Molecular Similarity Indices Analysis (CoMSIA) were performed on the series of 2-(2-(benzylthio)-1H-benzo[d]imidazol-1-yl) acetic acids derivatives. Initially, GASP module was used for generation of pharmacophore models using five highly active compounds from the dataset. Among the generated pharmacophores, the best pharmacophore model was selected based on fitness score and was used as template for the alignment of compounds which was used for CoMSIA analysis. The best predictions were obtained utilizing steric, hydrophobic and H-bond acceptor parameters showing a $q^2$=0.559 and $r^2$=0.730. 15 test set compounds was used to investigate the predictive ability of the CoMSIA model. Contour maps suggested that presence of bulky substituents and H-bond acceptor atoms at $5^{th}$ position of benzene ring will increase the activity of the compounds. The results obtained from this study will be useful to design more potent CRTh2 antagonists.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.389-396
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• 2010

In this paper, a new computational code was developed using Chorin's artificial compressibility method to solve the two-dimensional incompressible Navier-Stokes equations. In spatial derivatives, Roe's flux difference splitting was used for the inviscid flux, while central differencing was used for the viscous flux. Furthermore, AF-ADI with dual time stepping method was implemented for accurate unsteady computations. Two-equation turbulence models, Menter's $k-{\omega}$ SST model and Coakley's $q-{\omega}$ model, hae been adopted to solve high-Reynolds number flows. A number of numerical simulations were carried out for steady laminar and turbulent flow problems as well as unsteady flow problem. The code was verified and validated by comparing the results with other computational results and experimental results. The results of numerical simulations showed that the present developed code with the artificial compressibility method can be applied to slve steady and unsteady incompressible flows.

• Molecular & Cellular Toxicology
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• v.5 no.1
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• pp.14-22
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• 2009

In vitro cytotoxicity of 23 alkyl phenols (APs) on human cervical cancer cell lines (HeLa) was determined using the lactate dehydrogenase (LDH) cytotoxicity assay. Two different sets of descriptors were used to construct the calibration model based on Genetic Algorithm-Multiple Linear Regression (GA-MLR) based on the experimental data. A statistically robust Structure-Activity Relationships (QSAR) model was achieved ($R^2$=95.05%, $Q^2_{LOO}$=91.23%, F=72.02 and SE= 0.046) using three Dragon descriptors based on Me (0D-Constitutional descriptor), BELp8 (2D-Burden eigenvalue descriptor) and HATS8p (3D-GETAWAY descriptor). However, external validation could not fully prove its validity of the selected QSAR in characterization of the cytotoxicity of APs towards HeLa cells. Nevertheless, the cytotoxicity profiles showed a finding that 4-n-octylphenol (4-NOP), 4-tert-octyl-phenol (4-TOP), 4-n-nonylphenol (4-NNP) had a more potent cytotoxic effect than other APs tested, inferring that increased length and molecular bulkiness of the substituent had important influence on the LDH cytotoxicity.

• Wind and Structures
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• v.14 no.3
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• pp.253-283
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• 2011

This paper presents the field measurement results of wind effects on a super-tall building (CITIC Plaza, 391 m high) located in Guangzhou. The field data such as wind speed, wind direction and acceleration responses were simultaneously and continuously recorded from the tall building by a wind and vibration monitoring system during two typhoons. The typhoon-generated wind characteristics including turbulence intensity, gust factor, peak factor, turbulence integral length scale and power spectral density of fluctuating wind speed were presented and discussed. The dynamic characteristics of the tall building were determined based on the field measurements and compared with those calculated from a 3D finite element model of the building. The measured natural frequencies of the two fundamental sway modes of the building were found to be larger than those calculated. The damping ratios of the building were evaluated by the random decrement technique, which demonstrated amplitude-dependent characteristics. The field measured acceleration responses were compared with wind tunnel test results, which were found to be consistent with the model test data. Finally, the serviceability performance of the super-tall building was assessed based on the field measurement results.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4352-4360
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• 2011

A four dimensional quantitative structure activity relationship analysis was applied to a series of 50 flavonoid inhibitors of $p56^{lck}$ protein tyrosine kinase by the molecular comparative electron topological method. It was found that the -log (IC50) values of the compounds were highly dependent on the topology, size and electrostatic character of the substituents at seven positions of the flavonoid scaffold in this study. Depending on the negative or positive charge of the groups correctly embedded in these substituents, three-dimensional bio-structure to increase or decrease -log (IC50) values in the training set of 39 compounds was predicted. The test set of 11 compounds was used to evaluate the predictivity of the model. To generate 4D-QSAR model, the defined function groups and pharmacophore used as topological descriptors in the calculation of activity were of sufficient statistical quality ($R^2$ = 0.72 and $Q^2$ = 0.69). Ligand docking approach by using Dock 6.0. These compounds include many flavonoid analogs, They were docked onto human families of p56lck PTKs retrieved from the Protein Data Bank, 1lkl.pdb.

• Journal of Integrative Natural Science
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• v.8 no.2
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• pp.89-98
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• 2015

Chemoattractant receptor homologous molecule expressed on Th2 cells (CRTh2) is a G-protein coupled receptor targeted for inflammatory diseases such as asthma, allergic rhinitis and atopic dermatitis. In this study, pharmacophore modeling and comparative molecular field analysis (CoMFA) were performed on the series of 2-(2-(benzylthio)-1H-benzo[d]imidazol-1-yl) acetic acids derivatives. Five highly active compounds were used for generation of pharmacophore models using GASP module. The best pharmacophore model was selected and used as template for the alignment of compounds which was used for CoMFA analysis. The best predictions obtained for CoMFA was $q^2=0.545$, $r^2=0.756$. The predictive ability of the model was investigated using 15 test set compounds. Contour maps suggested that presence of bulky substituents at $5^{th}$ position of benzene ring connected to suphur atoms attached to imidazol ring will increase the activity of the compounds. The results obtained from this study will be useful to design more potent CRTh2 antagonists.

• Journal of computational fluids engineering
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• v.20 no.4
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• pp.1-6
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• 2015

Centrifugal pumps consume considerable amount of energy in various industrial applications. Therefore, improvement of the efficiency of these machines has become a major challenge. Cavitation is a phenomenon which decreases the pump efficiency and even causes structural demage. Hence, the goal of this paper is to investigate the cavitation problem in the single-stage and double-stage centrifugal pumps. The Volume of Fraction (VOF) method has been used for the numerical simulations together with Rayliegh-Plesset model for the gas-liquid two-phase flow inside the pump. In order to capture the turbulent phenomena, the standard k-${\varepsilon}$ turbulence model has been adopted, and the simulations have been done as unsteady cases. In addition, the motion of the rotating parts has been simulated using Multi Reference Frame(MRF) method. The results are presented and compared in terms of hydraulic head and NPSH for both the single-stage and double-stage pumps. The H-Q curves show the effects of cavitation on decreasing the pumps performances.

• KIEAE Journal
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• v.13 no.1
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• pp.151-157
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• 2013

Since high-rise building construction sites are usually located in crowded city areas, sufficient spaces for the inventories of key materials are rarely available. This spatial constraints have been one of the critical challenge that may cause productivity loss and increasing costs of the high-rise building construction projects. The proper material inventory management is certaing a key to the success of high-rise building construction projects as it handles difficulty of securing material stock yards, changes in demands, uncertain delivery time through integrating the construction schedules and actively responding to the key materials attributes. In this light, this research analyzes the latest inventory model, (Q,r) model, in accordance with the high rise building characteristics. This research suggests an optimal inventory management of re-bar considering various demands and lead times. The case study is also presented with regard to the re-bar inventory management.