• Asian-Australasian Journal of Animal Sciences
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• v.17 no.3
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• pp.343-348
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• 2004

The objective of the present study was to determine the plasma level of insulin-like growth factor-I (IGF-I) in relation to mammary blood flow and milk yield including biological variables of relevance to milk synthesis in two different types of crossbred Holstein cattle at 3 different stages of lactation. Eight heifers were 87.5% HF and eight 50% HF animals were selected for the experiments. The three stages of lactation tested were: early lactation (30 days postpartum), mid-lactation (120 days postpartum) and late lactation (210 days postpartum). Animals in each group were fed a concentrate and rice straw treated with 5% urea as the source of roughage throughout the experiments. In early lactation, mammary blood flow and milk yield of 87.5% HF animals were significantly higher than those of 50% HF animals. In mid- and late lactation, both mammary blood flow and milk yield showed a proportional decrease from the early lactating period of 87.5% HF animals. The trends for persistency were observed in 50% HF animals as for udder blood flow and milk yield throughout the experimental periods. The plasma glucose level of the 50% HF animals was significantly higher than those of 87.5% HF animals in both early and mid-lactation. The concentrations of arterial plasma free fatty acids ($C_{16}\;to\;C_{18}$) were higher in 50% HF animals as compared with 87.5% HF animals in all periods of study. In early lactation, the concentration of plasma growth hormone (GH) of 87.5% HF animals was higher than those of the 50% HF animals, thereafter the mean level of plasma growth hormone declined in both mid- and late lactation. The concentration of plasma IGF-I of 50% HF animals was significantly higher than those of 87.5% HF animals in all stages of lactation. There were no differences among stages of lactation for the levels of plasma IGF-I, insulin and growth hormone in 50% HF animals. In 87.5% HF animals, the plasma levels of both IGF-I and insulin were lower in early lactating period while it showed an increase during mid- and late lactation. The present results indicated that the regulatory role for the higher mammary blood flow and milk yield during lactation in 87.5% HF are not mediated via the higher level of circulating IGF-I. Differences in mammary blood flow and milk yield between 50% HF and 87.5% HF animals are in part due to a higher concentration of circulating growth hormone. The lower level of circulating growth hormone in 50% HF animals would be regulated by higher levels of IGF-I, free fatty acid and glucose in plasma.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.362-365
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• 2002

Hf thin films were deposited on bottom metal using a RF magnetron sputtering method followed by oxidation and annealing in O$_2$ and N$_2$ ambient, respectively. Various top metal electrodes (i.e., Al, Au, and Cu) were deposited by evaporation, and their roles on physical and electrical properties were investigated. Using the XRD, SEM and AFM techniques, we confirmed that the grain size of HfO$_2$ thin films enlarges as a function of oxidation temperature, increasing dielectric constant. However, other electrical properties (e.g., tan) deteriorateas a consequence. The dielectric constant and tan of HfO$_2$ thin films oxidized at 500 $^{\circ}C$ were 17-25 and 3${\times}$10-3 - 2x10-2, respectively, in the frequency range of 1 Hz to 1 MHz. The leakage current density was less than 1${\times}$10-8A/cm2 up to 0.7 MV/cm. In addition, electrical properties of HfO$_2$ thin films (e.g., the dielectric constant, leakage current and tan $\delta$) depend on top metal electrode. We showed that Al top metal electrode results in the best result.

• Journal of Food Hygiene and Safety
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• v.33 no.4
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• pp.316-323
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• 2018

The purpose of the present study was to investigate the effect of Salvia Plebia R. Br. (SP) powder on the antioxidative defense system and oxidative stress in rats which were fed a high fat high cholesterol diet. Accordingly, the rats were divided into four experimental groups which were composed of a high fat high cholesterol diet group (HF), HF diet with 5% SP powder supplemented group (PA), a HF diet with 10% SP powder supplemented group (PB), and a normal group (N). Consequently, the hepatic catalase activity of the HF group was decreased compared to the normal group (N), but it is recorded that of the PA and PB groups were significantly increased. With this in mind, the PA and PB groups resulted in the case of significantly increased activities of hepatic GSH-px and SOD. The hepatic superoxide radical and hydrogen peroxide contents of the PA and PB groups were significantly decreased, as compared to the HF group. The GOT and GPT activities of the PB group were also significantly decreased when thus compared to the HF group. Notably, the carbonyl values contents of the PA and PB groups were significantly reduced compared to the HF group. The hepatic TBARS values in the liver were significantly reduced as measured in the PA and PB groups. These results suggest that the SP powder may reduce the incidence of oxidative damage, by the activation of an antioxidative enzyme in rats fed with high fat high cholesterol diets.

• Preventive Nutrition and Food Science
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• v.11 no.1
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• pp.48-53
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• 2006

Although garlic has been reported to have impressive effects in lowering serum lipids, there have been controversial evaluations on these effects. To find the potential fator causing the inconsistency in the previous studies, we examined the effects of two types of garlic according to the producing-area (hangihyung garlic, nangihyung garlic) on serum lipid profiles and leptin level. Thirthy six of 4 wk old Sprague Dawley male rats fed high fat diet (40% of calories as fat) for 6 wks to induce obesity, and subsequently fed 5% garlic powder supplemented (HF+H: hangihyung garlic powder, HF+N: nangihyung garlic powder) high fat diets (w/w) for further 5 wk. For the comparison, normal control group fed AIN-76A diet (11.7% of calories as fat). Supplementation with hangihyung and nangihyung garlic resulted in a significant reduction of high fat induced body weight gain, white fat (i.e., epididymal, visceral and peritoneal fat) development, adipocyte hypertrophy and the development of hyperinsulinemia and hyperliptinemia. Serum triglyceride and total cholesterol level was greatly reduced by hangihyung garlic supplementation (p<0.05). The HDL-cholesterol level was increased by dietary hangihyung and nangihyung garlic. There were slight non-significant decreases in triglyceride and total cholesterol of HF+N group as compared to those of HF group. Leptin level of HF+H group was found to be significantly lower than HF group (p<0.05). There was no significant difference among N group and HF+N group. These results suggest that hangihyung garlic may lead to the higher activity in improving lipid profiles than nangihyung garlic. Whether the hypolipidemic effect of garlic increases in a species-dependent has yet to be determined and awaits further research.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.04a
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• pp.71-72
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• 2007

In this study, we investigated the fabrication of MLR (multi-layer resist) with a very thin diamond-like carbon (DLC) layer. ArF PR/$SiO_2$/DLC MLR structure was investigated and etching characteristics of the DLC layer was patterned using $SiO_2$ hard-mask by varying the process parameters such as different high-frequency/low-frequency combination ($f_{LF}/f_{HF}$), HF/LF power ratio ($P_{HF}/P_{LF}$), $O_2$ flow and $N_2$ flow rate in $O_2/N_2$/Ar plasmas. The results indicated an increased etch rate of DLC for the higher $f_{LF}/f_{HF}$ combination and for the increased low-frequency power ($P_{LF}$). And the etch rate of DLC was decreased with increasing the $N_2$ flow rate in $O_2/N_2$/Ar plasmas. In order to confirm the application of DLC MLR for the etching process of silicon oxide, the stack of ArF PR/BARC/$SiO_2$/DLC/TEOS/Si was investigated.

• Korean Journal of Ecology and Environment
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• v.47 no.1
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• pp.13-23
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• 2014

To obtain optimum filter media, configuration method and greenhouse wastewater loading in small-scale constructed wetlands (CWs) for treating greenhouse wastewater, the apparatuses were constructed with 4 kinds of combined systems such as vertical flow (VH)-Horizontal flow (HF), HF-VH, HF-VF-HF, VF-HF-HF CWs. The efficiencies of pollutants in greenhouse wastewater were investigated in various CWs under different filter media, configuration methods and agricultural water loading. Removal rates of pollutants under different filter media were in the other of coarse sand>broken stone${\fallingdotseq}$calcite${\fallingdotseq}$mixed filter media for COD, broken stone>mixed filter media>coarse sand>calcite for T-N, and calcite>mixed filter media>broken stone>coarse sand for T-P. The removal rates of pollutants in HF-VH-HF CWs at different configuration methods were higher than those in other configuration methods. The removal rates of pollutants were higher in the order of $150L\;m^{-2}day^{-1}{\fallingdotseq}300L\;m^{-2}day^{-1}$ > $600L\;m^{-2}day^{-1}$ under different greenhouse wastewater loading. Therefore, optimum configuration method was HF-VH-HF CWs, the optimum filter media was mixed filter media (coarse sand : broken stone : calcite=1 : 1 : 1), and the optimum greenhouse wastewater loading was $300L\;m^{-2}day^{-1}$ in HF-VH-HF CWs.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.04a
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• pp.45-46
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• 2007

역전파 신경망은 반도체 공정 모델링에 효과적으로 응용되고 있으며, 모델의 예측정확도를 향상시키기 위하여 Random Generator를 개발하였다. Random Generator의 효과가 기존이 모델에 비해 예측정확도의 향상에 영향을 주었음을 알 수 있었다. 모델링에 이용한 실험데이터는 다중 유도결합형 플라즈마 장비를 이용하여 수집하였다.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.3
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• pp.334-347
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• 2000

The present experiment was carried out to study the utilization of glucose in the mammary gland of crossbred Holstein cattle during feeding with different types of roughage. Sixteen first lactating crossbred Holstein cattle which comprised eight animals of two breed types, Holstein Friesian${\times}$Red Sindhi ($50{\times}50=50%$ HF) and Holstein Friesian${\times}$Red Sindhi ($87.5{\times}12.5=87.5%$ HF). They were divided into four groups of 4 animals each of the same breed. The utilization of glucose in the mammary gland was determined by measuring rates of glucose uptake and the incorporation of glucose into milk components in both groups of 50% HF and 87.5% HF animals feeding on either hay or urea treated rice straw. In early lactation, there were no significant differences of the total glucose entry rate and glucose carbon recycling among groups of crossbred animals feeding on either hay or urea treated rice straw. During lactation advance, the total glucose turnover rates and recycling of carbon glucose of crossbred HF animals feeding on urea treated rice straw were markedly higher than those of crossbred HF animals feeding on hay as roughage, whereas there were no significant changes for both groups of crossbred animals feeding on hay. The percentages and values of non-mammary glucose utilization showed an increase during lactation advance in the same group of both 50% HF and 87.5% HF animals. The percentage of glucose uptake for utilization in the synthesis of milk lactose by the mammary gland was approximately 62% for both groups of 87.5% HF and by approximately 55% for both groups of 50% HF animals feeding on either hay or urea treated rice straw. Intracellular glucose 6-phosphate metabolized via the pentose phosphate pathway accounted for the NADPH (reducing equivalent) of fatty acid synthesis in the mammary gland being higher in 87.5% HF animals during mid-lactation. A large proportion of metabolism of glucose via the Embden-Meyerhof pathway in the mammary gland was more apparent in both groups of 50% HF animals than those of 87.5 % HF animals during early and mid-lactation while it markedly increased for both groups of 87.5% HF animals during late lactation. It can be concluded that utilization of glucose in the mammary gland occurs in a different manner for 50% HF and 87.5% HF animals feeding on either hay or urea treated rice straw. The glucose utilization for biosynthetic pathways in the mammary gland of 50% HF animals is maintained in a similar pattern throughout the periods of lactation. A poorer lactation persistency in both groups of 87.5% HF animals occurs during lactation advance, which is related to a decrease in the lactose biosynthetic pathway.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.477-477
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• 2008

For more than three decades, the gate dielectrics in CMOS devices are $SiO_2$ because of its blocking properties of current in insulated gate FET channels. As the dimensions of feature size have been scaled down (width and the thickness is reduced down to 50 urn and 2 urn or less), gate leakage current is increased and reliability of $SiO_2$ is reduced. Many metal oxides such as $TiO_2$, $Ta_2O_4$, $SrTiO_3$, $Al_2O_3$, $HfO_2$ and $ZrO_2$ have been challenged for memory devices. These materials posses relatively high dielectric constant, but $HfO_2$ and $Al_2O_3$ did not provide sufficient advantages over $SiO_2$ or $Si_3N_4$ because of reaction with Si substrate. Recently, $HfO_2$ have been attracted attention because Hf forms the most stable oxide with the highest heat of formation. In addition, Hf can reduce the native oxide layer by creating $HfO_2$. However, new gate oxide candidates must satisfy a standard CMOS process. In order to fabricate high density memories with small feature size, the plasma etch process should be developed by well understanding and optimizing plasma behaviors. Therefore, it is necessary that the etch behavior of $HfO_2$ and plasma parameters are systematically investigated as functions of process parameters including gas mixing ratio, rf power, pressure and temperature to determine the mechanism of plasma induced damage. However, there is few studies on the the etch mechanism and the surface reactions in $BCl_3$ based plasma to etch $HfO_2$ thin films. In this work, the samples of $HfO_2$ were prepared on Si wafer with using atomic layer deposition. In our previous work, the maximum etch rate of $BCl_3$/Ar were obtained 20% $BCl_3$/ 80% Ar. Over 20% $BCl_3$ addition, the etch rate of $HfO_2$ decreased. The etching rate of $HfO_2$ and selectivity of $HfO_2$ to Si were investigated with using in inductively coupled plasma etching system (ICP) and $BCl_3/Cl_2$/Ar plasma. The change of volume densities of radical and atoms were monitored with using optical emission spectroscopy analysis (OES). The variations of components of etched surfaces for $HfO_2$ was investigated with using x-ray photo electron spectroscopy (XPS). In order to investigate the accumulation of etch by products during etch process, the exposed surface of $HfO_2$ in $BCl_3/Cl_2$/Ar plasma was compared with surface of as-doped $HfO_2$ and all the surfaces of samples were examined with field emission scanning electron microscopy and atomic force microscope (AFM).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.34-34
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• 2009

The electrical characteristics of tunnel barrier engineered charge trap flash (TBE-CTF) memory with $SiO_2/Si_3N_4/SiO_2/Si$ engineered tunnel barrier, $HfO_2$ charge trap layer and $Al_2O_3$ blocking oxide layer (MAHONOS) were investigated. The energy bad diagram was designed by using the quantum-mechanical tunnel model (QM) and then the CTF memory devices were fabricated. As a result, the best thickness combination of MAHONOS is confirmed. Moreover, not enhanced P/E speed (Program: about $10^6$ times) (Erase: about $10^4$ times) but also enhanced retention and endurance characteristics are represented.