• Korean Journal of Animal Reproduction
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• v.16 no.4
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• pp.387-397
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• 1993

To examine local response of adenosie(purine nucleoside) on the developing mammary gland, Elvax 40P implants containing adenosine were surgically implanted into mammary fat pad of the five week old female ICR mice. Inguinal(the 4th) mammary glands of anesthetized mice were exposed andplaced the implants for 12 days. One gland was treated with an adenosine implant, while the contralateral gland received a blank implant as control. For whole-mount preparations, glands were stained with alum carmine, and for histological observation, micro-selected mammary glands were stained with hematoxylin and eosin Y. Implantation with Elvax 40P did not affect on the damage of neighboring mammary tissue. Adenosie 25 or 250$\mu\textrm{g}$ per slow-release implant stimulated local mammary end bud formation of ovariectomized mice such as end bud size and numbers of end bud per gland in a dose dependent manner(P<0.05), and lower concentration of adenosie(2.5 or 25$\mu\textrm{g}$/implant) increased numbers of end bud(P<0.05) and end bud size(P<0.1) of intact mice. Adenosine treatment and intact ovarian function had moderate interation effects on the stimulation of end bud formation at 2.5$\mu\textrm{g}$ adenosine/implant(P<0.1). In histological observation, adenosine implants increased numbers of mammary epithelial type of cells at mammary duct in the presence or absece ofovary. These results indicate that adenosine should be one of regulators in mouse mammary ductal growth.

• Journal of the Korean Society for Advanced Composite Structures
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• v.6 no.2
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• pp.85-90
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• 2015

The finite element stress analysis of large sized rectangular water tank structures made of stainless steel materials is carried out for various combined load cases. The combined load cases for a large size of 5,000ton are further determined using the specification(KS B6283) established from the Korean Standards Association. The changed water capacity due to the size of reservoirs could be heavily dependent for evaluating seismic effects, especially for large reservoirs. For the better numerical efficiency, the rectangular panels are modelled using the ANSYS ADPL module. The numerical results obtained for different load cases mainly show the effect of the interactions between the different load combination and other various parameters, for example, the water capacity, and different stainless steel materials. The structural performance for various load combinations is also evaluated.

• The Journal of Asian Finance, Economics and Business
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• v.3 no.4
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• pp.25-37
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• 2016

This study aims to investigate the determinants of dividend payout of Oil and Gas industry of Pakistan using secondary data from published annual reports from 2008 to 2014 listed on KSE (Karachi Stock Exchange). Dividend payout can be affected by profitability, firm size, financial leverage, sales growth, investment opportunities, liquidity, business risk, and ownership structure. Panel data technique used due to panel characteristics of available data with ordinary least square regression model to find out the impact of set of explanatory variables on the dividend payout using the Stata. Financial leverage, sales growth and business risks are the most significant variables of the study where financial leverage and business risk have significant negative effect on dividend payout while sales growth has favorable positive impact on dividend payout. Results revealed significant positive link of profitability and firm size with dividend payout whereas government ownership is negatively associated with dividend payout. Investment opportunities, liquidity and managerial ownership showed insignificant relationship with dividend payout. This Suggests that dividend payout policy is dependent on business strategies including both investment and financing decisions. Financial managers should consider these factors while formulating dividend policy of the firm.

• Journal of the Korean Society for Railway
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• v.10 no.6
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• pp.786-791
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• 2007

Aerodynamically generated noise is dominant when the train speed approaches 300km/h. This noise sources is caused by the turbulent flow separations or vortex shedding from the train structure. Experiments were performed to investigate the characteristics of aerodynamic noise sources generated from exterior of the KTX trains and HSR-350x, especially from the inter-coach spacing. Measurements of both the inside and outside of the cabin are carried out to investigate the characteristics of the noise. Effect of the size of the mud-flap has been investigated through an wind tunnel test and it has been found that the low frequency noise is strongly dependent on the size of the gap. Also performed is an array measurement to locate different noise sources from the high-speed train. spectral characteristics of exterior noise sources are examined.

• Membrane Journal
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• v.6 no.2
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• pp.109-116
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• 1996

This work is a fundamental study for applying hybrid process coupling adsorption with microfiltration to waste-water treatment. Phenol was separated by adsorption on powdered activated carbon, adsorbed phenol with activated carbon was separated by microfiltration. As the particle size in suspension increased, filtration resistance decreased, and effect of particle concentration on resistance was less pronounced. The rate of uptake was greatly dependent on the degree of phenol loading. For a smaller amounts of activated carbon, the change of permeate concentration before break point and phenol loading with time were steeper than in the case of large amounts. Permeate concentration before break point decreased with decreasing particle size, this could be due to the increase of outer surface of particle and film mass transfer coefficient.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.11
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• pp.1509-1517
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• 1997

Charged and uncharged particle motions and collection characteristics around a bipolar charged rectangular shape electret fiber are studied numerically. Particle inertia, fluid drag, Coulomb force and polarization force are considered to predict the particle motion around the electret fiber. The effects of particle sizes, flow velocities, number of charges and polarities are also systematically investigated. For small size particles, the single fiber collection efficiency is greatly dependent on the charge polarity and the number of charges on a particle. However, particles larger than 5.mu.m do not show charging effect on collection efficiencies in the flow velocity ranges from 1.5 cm/s to 150 cm/s when the maximum charges are within +5 to -10. The results show that a strong electric field gradient at the corner of the bipolar charged fiber plays a very important role on collecting particles regardless of its charge polarity because of the polarization force. It also shows that the most penetrating particle size for a single electret fiber decreases as the flow velocity increases and the number of charges of a particle decreases.

• Archives of Pharmacal Research
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• v.22 no.4
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• pp.384-390
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• 1999

Thirty-four glutathione conjugates of 5,8-dimethoxy-1,4-naphthoquinones (DMNQ) were synthesized and their structure was determined. The yield of GSH conjugate was dependent on size of alkyl group; the longer the size of alkyl group was, the lower was the yield. It was also found that the length of alkyl side chain influenced the chemical shift of quinonoid protons; the quinonoid protons of 2-glutathionyl DMNQ derivatives with R=H to propyl, 6.51-6.59 ppm vs. other ones with R=butyl to heptyl, 6.64-6.68 ppm. this was explained to be due to a folding effect of longer alkyl group. Glutathione (GSH) reacted with DMNQ derivative first to form a 1,4-adduct (2- or 3-glutathionyl-1,4-dihydroxy-5,8-dimethoxynaphthalenes) and then the adduct was autooxidized to 2- or 3-glutathionyl-DMNQ derivatives. Moreover, GSH reduced DMNQ derivatives to their hydrogenated products. It was suggested that such an organic reaction might play an important role for a study of metabolism or toxicity of DMNQ derivative sin the living cells.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.5
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• pp.441-447
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• 2003

When a SnO$_2$ thin film was deposited by thermal CVD, two different types of growth behavior that were dependent on the deposition temperature were observed. The film grown at 475$^{\circ}C$ had a wide grain size distribution and a faceted surface shape. On the other hand, the film grown at 5$25^{\circ}C$ had a relatively narrow grain size distribution and a rounded sulfate shape. The aspects of grain shape and growth behavior agree well with the theory of gram growth and a roughening transition. The charge tarrier density decreased with deposition time. According to photoluminescence measurements, the peak intensity of the spectra occurred at approximately 2.5 eV, which is related to oxygen vacancies, and decreased with increasing of deposition time. These measurement results suggest that the number of oxygen vacancies, which is related to the electrical conductivity, decrease with deposition time.

• Journal of Nutrition and Health
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• v.24 no.5
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• pp.431-441
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• 1991

To investigate the influence of age and dietary fat level on the immune function and the growing potential of the fibroblast cells, male rats of 2 month, 6 month and 30 month of age were fed either 6% or 30% fat diet for 16 weeks. The weight of thymus decreased linearly with increasing age. And this age-dependent degeneration of thymus was delayed in rats fed low fat diets. The blastogenesis of spleen lymphocytes to PHA, ConA, and PWM was decreased with increasing age, however, no effect of dietary fat level was observed. The age-related decline in ratios of PHA/ConA response may suggest that T suppressor cell activity increases with age. In cell culture system, lung fibroblast cells from 30M rats showed lower plating efficiency. longer doubling time. and shorter cumulative doubling potential than those from 2M or 6M animals. Also. the morphology of fibroblasts from 30M rats was tended to be rouned rather than flattened and more variable in size and being generally larger. wherease those from 2M and 6M rats were uniform in size and adhered tightly to the culture vessel in ordered arrays. Therefore fibroblast cell culture system tried in this study reflects the changes of cellular aging.

• Advances in nano research
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• v.8 no.1
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• pp.13-24
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• 2020

In this paper, for the first time based on the nonlocal strain gradient theory the effect of size dependency in torsional vibration of bi-direction functionally graded (FG) nonlinear nano-cone is study. The material properties were assumed to vary according to the arbitrary function in radial and axial directions. The Navier equation and boundary conditions of the size-dependent bidirectional FG nonlinear nano-cone were derived by Hamilton's principle. These equations were solved by employing the generalized differential quadrature method (GDQM). The presented model can turn into the classical model if the material length scale parameters are taken to be zero. The effects of some parameters, such as inhomogeneity constant, cross-sectional area parameter and small-scale parameters, were studied. As an essential result of this study can be stated that an FG nano-cone model based on the nonlocal elasticity theory behaves softer and based on the strain gradient theory behaves harder.