• Asian-Australasian Journal of Animal Sciences
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• v.26 no.2
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• pp.266-274
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• 2013

The effect of different phytogenic feed additives on reducing odorous compounds in swine was investigated using in vitro fermentation and analyzed their microbial communities. Soybean meal (1%) added with 0.1% different phytogenic feed additives (FA) were in vitro fermented using swine fecal slurries and anaerobically incubated for 12 and 24 h. The phytogenic FAs used were red ginseng barn powder (Panax ginseng C. A. Meyer, FA1), persimmon leaf powder (Diospyros virginiana L., FA2), ginkgo leaf powder (Ginkgo biloba L., FA3), and oregano lippia seed oil extract (Lippia graveolens Kunth, OL, FA4). Total gas production, pH, ammonianitrogen ($NH_3$-N), hydrogen sulfide ($H_2S$), nitrite-nitrogen ($NO_2{^-}$-N), nitrate-nitrogen ($NO_3{^-}$-N), sulfate (${SO_4}^{--}$), volatile fatty acids (VFA) and other metabolites concentration were determined. Microbial communities were also analyzed using 16S rRNA DGGE. Results showed that the pH values on all treatments increased as incubation time became longer except for FA4 where it decreased. Moreover, FA4 incubated for 12 and 24 h was not detected in $NH_3$-N and $H_2S$. Addition of FAs decreased (p<0.05) propionate production but increased (p<0.05) the total VFA production. Ten 16S rRNA DGGE bands were identified which ranged from 96 to 100% identity which were mostly isolated from the intestine. Similarity index showed three clearly different clusters: I (FA2 and FA3), II (Con and FA1), and III (FA4). Dominant bands which were identified closest to Eubacterium limosum (ATCC 8486T), Uncultured bacterium clone PF6641 and Streptococcus lutetiensis (CIP 106849T) were present only in the FA4 treatment group and were not found in other groups. FA4 had a different bacterial diversity compared to control and other treatments and thus explains having lowest odorous compounds. Addition of FA4 to an enriched protein feed source for growing swine may effectively reduce odorous compounds which are typically associated with swine production.

• Korean Journal of Poultry Science
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• v.28 no.3
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• pp.289-295
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• 2001

The objectives or this study were to improve duck meat qualify during storage period in onion-red ducks which contained antioxidants. Experimental animals (1 day old, Cherry Valley $F_{1}$, 360 chicks) were randomly assigned in eight treatment group. Treatments were control, 3%, 6% of chopped onion-fed, 5%, 10% of onion extract fed, 6% of onion meal, 3%, 6% of fermented onion-fed. pH was significantly high (P<0.05) in treatment group after 3 day storage in pectoralis muscle. Meat color was low in r* and a* value. TBA value was not different in day 1, was significantly low (P<0.05) 6% chopped and 6% fermented group after day 3 storage. Also, TBA value was significantly high (P<0.05) in control group and was significantly low in 3% chopped, 5%, 10% extract after day 6 storage. VBN value was lower in all treatment groups except 5% ferment group than control group. Meat order was high score in 3% and 6% chopped group and duck specific smell was reduced in all treatment groups. Meat appearance was higher score in treatment groups than in control group during 9 day storage. In result, onion feeding was reduce duck specific smell and improve meat quality during long period storage in ducks.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1519-1523
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• 2006

Through a screening and selection approach method, decamer random markers were used in a technique called random amplified polymorphic DNA (RAPD) assay with 252 genomic DNAs isolated from four major Haimen chicken populations: Rugao (62), Jiangchun (62), Wan-Nan (63) and Cshiqishi (65). A total of 3-score decamer random primers (S241-S260, S1081-S1100 and S1341-S1360) were employed in the preliminary RAPD-polymerase chain reaction (RAPD-PCR) assay with 50 random template DNA samples from all the populations. Four (6.67%) of the primers that produced obvious polymorphic patterns, interpretable and reproducible bands were selected and used with both the individual DNAs from each population and with pooled DNA samples of the four populations in subsequent analyses. The selected primers produced a total of 131 fragments with molecular size ranging from 835 to 4,972 base pairs (bp) when used with the individual DNAs; 105 (80.15%) of these fragments were polymorphic. With the pooled DNAs, 47 stable and characteristic bands with molecular size ranging from 840 to 4,983 bp, of which 23 (48.94%) polymorphic, were also generated. The band-sharing coefficient (BSC) calculated for the individuals in the population and among populations of bulked samples was between 0.8247 (Rugao) and 0.9500 (Cshiqishi); for pairwise populations, it was between 0.7273 (Rugao vs. Wan-Nan) and 0.9367 (Jiangchun vs. Cshiqishi) chicken populations. Using the BSC for individual and pairwise populations, the Nei's standard genetic distances between the chicken populations were determined and ranged from 0.0043 (Jiangchun vs. Cshiqishi) to 0.1375 (Rugao vs. Cshiqishi). The reconstructed dendrogram linked the Jiangchun and Cshiqishi chickens as closely related populations, followed by Wan-Nan, while the Rugao was the most genetically distant among the populations.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.79-79
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• 1999

The varous techniques for fabrication of si or metal tip as a field emission electron source have been reported due to great potential capabilities of flat panel display application. In this report, 240nm thermal oxide was initially grown at the p-type (100) (5-25 ohm-cm) 4 inch Si wafer and 310nm Si3N4 thin layer was deposited using low pressure chemical vapor deposition technique(LPCVD). The 2 micron size dot array was photolithographically patterned. The KOH anisotropic etching of the silicon substrate was utilized to provide V-groove formation. After formation of the V-groove shape, dry oxidation at 100$0^{\circ}C$ for 600 minutes was followed. In this procedure, the orientation dependent oxide growth was performed to have a etch-mask for dry etching. The thicknesses of the grown oxides on the (111) surface and on the (100) etch stop surface were found to be ~330nm and ~90nm, respectively. The reactive ion etching by 100 watt, 9 mtorr, 40 sccm Cl2 feed gas using inductively coupled plasma (ICP) system was performed in order to etch ~90nm SiO layer on the bottom of the etch stop and to etch the Si layer on the bottom. The 300 watt RF power was connected to the substrate in order to supply ~(-500)eV. The negative ion energy would enhance the directional anisotropic etching of the Cl2 RIE. After etching, remaining thickness of the oxide on the (111) was measured to be ~130nm by scanning electron microscopy.

• Korean Journal of Head & Neck Oncology
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• v.4 no.1
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• pp.29-34
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• 1988

Radiation therapy is generally considered to be the treatment of choice in $T_1$ glottic cancer, maninly because of preservation of voice function and its local control rate is comparable to that of surgery. Failures from radiation therapy can be ultimately salvaged by surgery. A retrospective analysis of the treatment of 25 patients with $T_1$ glottic cancer seen at the Yonsei Cancer Center from 1980 to 1984 is presented. Radiation dose to the target volume varied from 6400 to 7000 cGy in 6-7 weeks. The local control rate is 84%. Four patients had primary failure and three of these patients had salvage surgery. Of the 3 patients who had salvage surgery, 2 were cured and aonther one was died with progression of the disease. 5-year acturial and disease free survival rate are 91.1%,78.0% respectively.

• Journal of Animal Science and Technology
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• v.45 no.3
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• pp.355-368
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• 2003

In Exp. 1, this study was conducted to determine the effect of dietary germanium biotite on growth performance and nutrient digestibility in nursery pigs. A total of sixty crossbred pigs (initial body weight 15.09$\pm$0.18kg) were used in this experiment. This study was carried out for 28 days. The five treatments were control (CON; basal diet), GB0.1 (basal diet + germanium biotite 0.1%), GB0.3 (basal diet + germanium biotite 0.3%), GB0.6 (basal diet + germanium biotite 0.6%) and GB1.0 (basal diet + germanium biotite 1.0%). For overall period, ADG and Gain/feed were not significantly different among the treatments. In Exp. 2, a study was conducted to evaluate the effect of germanium biotite as a substitute for antibiotics in growing pigs. A total of fifty five crossbred pigs (initial body weight 32.47$\pm$0.9kg) were used in this experiment. The three treatments were negative control (NC: basal diet without antibiotic), positive control (PC: basal diet + 200ppm CTC) and GB0.3 (basal diet + germanium biotite 0.3%). Pigs fed PC (17%, 385 vs 451 g/d) and GB0.3 (14%, 385 vs 438 g/d) diets grew faster(P<0.05) than pigs fed NC diet. Pigs fed PC and GB0.3 diets resulted higher(P<0.05) ADFI than pigs fed CON diet. However, pigs fed GB0.3 diet had improved gain/feed compared to pigs fed NC diet(P<0.05). Apparent digestibility of DM and N by pigs fed PC and GB0.3 diets were greater(P<0.05) than those by pigs fed NC diet. In Exp. 3, a study was conducted to determine the effect of dietary germanium biotite on growth performance, plasma characteristics, backfat thickness and fecal ammonia gas concentration in finishing pigs. A total of seventy-two finishing pigs (initial body weight 78.56$\pm$1.32kg) were used in this experiment. The treatments included 1) Control (CON; basal diet) 2) GB1.0 (basal diet + germanium biotite 1.0%), 3) GB3.0 (basal diet + germanium biotite 3.0%). Pigs fed GB1.0 diet grew faster than pigs fed CON diet and GB0.3 diet (P<0.05). Also, pigs fed CON diet showed higher(p<0.05) ADFI than pigs fed GB3.0 diet. Pigs fed GB diets had improved gain/feed compared to pigs fed CON diet(P<0.05). Total?and VLDL concentrations in plasma of pigs fed GB diets treatments were significantly decreased compared to those in pig fed CON diet(P<0.05). However, HDL-cholesterol concentration in plasma of the pig was significantly increased compared to those in pigs fed CON diet (P<0.05). Pigs fed CON diet exerted higher(P<0.05) backfat thickness than pigs fed GB1.0 (5.4%, 27.19 vs 25.71mm) and GB3.0 (16.1%, 27.19 vs 22.81mm) diets. Feces from CON treatment were higher in fecal ammonia gas concentration than faces from pigs fed GB1.0 (64.1%, 17.00 vs 6.10mg/kg)and GB3.0 (61.8%, 17.00 vs 6.50mg/kg) treatments(P<0.05). In conclusion, the results suggest that the dietary addition of germanium biotite into diets for nursery pigs did not affect growth performance. The results also suggest the possibility of germanium biotite to replace antibiotic in diets for growing pigs. In finishing pigs, dietary supplementation of germanium biotite was an effective means for improving growth performance and for decreasing Total-and LDL+VLDL-plasma cholesterols, backfat and fecal ammonia gas concentration.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.260-267
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• 2010

As sloped farmland is subject to runoff and soil erosion and consequently require appropriate vegetative coverage to conserve soil and water, a field study was carried out to evaluate the impact of crop canopy coverage on soil loss and runoff from the experimental plot with three different textural types (clay loam, loam, and sandy loam). The runoff and soil loss were examined at lysimeters with 15% slope, 5 m in length, and 2 m in width for five months from May to September 2009 in Suwon ($37^{\circ}$ 16' 42.67" N, $126^{\circ}$ 59' 0.11" E). Red pepper (Capsicum annum L. cv. Daechon) seedlings were transplanted on three different dates, May 4 (RP1), 15 (RP2), and 25 (RP3) to check vegetation coverage. During the experimental period, the vegetation coverage and plant height were measured at 7 day-intervals and then the 'canopy cover subfactor' (an inverse of vegetation cover) was subsequently calculated. After each rainfall ceased, the amounts of soil loss and runoff were measured from each plot. Under rainfall events >100 mm, both soil loss and runoff ratio increased with increasing canopy cover subfactor ($R^2$=0.35, p<0.01, $R^2$=0.09, p<0.1), indicating that as vegetation cover increases, the amount of soil loss and runoff reduces. However, the soil loss and runoff were depending on the soil texture and rainfall intensity (i. e., $EI_{30}$). The red pepper canopy cover subfactor was more highly correlated with soil loss in clay loam ($R^2$=0.83, p<0.001) than in sandy loam ($R^2$=0.48, p<0.05) and loam ($R^2$=0.43, p<0.1) plots. However, the runoff ratio was effectively mitigated by the canopy coverage under the rainfall only with $EI_{30}$<1000 MJ mm $ha^{-1}hr^{-1}$ ($R^2$=0.34, p<0.05). Therefore, this result suggested that soil loss from the red pepper field could be reduced by adjusting seedling transplanting dates, but it was also affected by the various soil textures and $EI_{30}$.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.2
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• pp.95-102
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• 2001

Nano-scale gate length MOSFET devices require extremely shallow source/drain eftension region with junction depth of 20∼30nm. In this work, 20nm $n^{+}$-p junctions that are realized by using this $As_{2}^{+}$ low energy ($\leq$10keV) implantation show the lower sheet resistance of the $1.0k\Omega$/$\square$ after rapid thermal annealing process. The $As_{2}^{+}$ implantation and RTA process make it possible to fabricate the nano-scale NMOSFET of gate length of 70nm. $As_{2}^{+}$ 5 keV NMOSFET shows a small threshold voltage roll-off of 60mV and a DIBL effect of 87.2mV at 100nm gate length devices. The electrical characteristics of the fabricated devices with the heavily doped and abrupt $n^{+}$-p junctions ($N_{D}$〉$10^{20}$$cm^{-3}$, $X_{j}$$\leq$20nm) suggest the feasibility of the nano-scale NMOSFET device fabrication using the $As_{2}^{+}$ low energy ion implantation.

• Journal of The Korean Association For Science Education
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• v.17 no.3
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• pp.301-311
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• 1997

The purpose of this study is to construct a structural equation model and to analyze causal relationships among variables related to attitudes to science using structural equation modeling(SEM) with LISREL VII. The sample consisted of 483 10th grade boys from a general high school in Pusan, Korea. The questionnaires (ABC-attitude scale: affection, behavioral intention, cognition scale of attitude towards science) were developed by the researcher through a pilot study. And other instruments have modified previous ones. Five instruments were used in this study: GALT(group assessment of logical thinking), MTSlS(modified test of science inquiry skill), ABC-attitude scale, MSAS(modified scientific attitude scale), CSAT(common science achievement test). Structural equation modeling with LISREL VII($J\ddot{o}reskog$ & $S\ddot{o}rbom,$ 1993) was employed to estimate the causal inferences about hypothesized relationships among observed data sets. Three competing models consisted of five latent variable(scientific thinking ability, science inquiry skill, attitude towards science, scientific attitude, science achievement) - lP(inquiry preceding) model, AP(attitude preceding) model and AM(attitude mediating) model - were developed. Among these competing models, IP model satisfied the observed data sets. The causal relationships among "attitudes to science" and other latent variables were reliably identified. According to the results of the present study, science inquiry skill was the most significant variable that can predict science achievement. But scientific thinking ability has not directly influenced science achievement. This study suggests that inquiry based teaching-learning processes should be offered to students for improvement of science achievement. At the same time, it seems to be important to develop positive attitude towards science. Understanding of relationships among variables related to attitudes to science will be helpful to the development of science curriculum and to the design of science teaching and learning process. LISREL has been recognized as a useful approach in testing a SEM. However, in this study, LISREL approach was estimated as much more useful method for research design.

• Proceedings of the Korean Vacuum Society Conference
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• 1996.06a
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• pp.40-41
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• 1996

Nitridation technique has been receiving much attention for the formation of a thin nitrided buffer layer on which high quality nitride films can be formedl. Particularly, gallium nitride (GaN) has been considered as a promising material for blue-and ultraviolet-emitting devices. It can also be used for in situ formed and stable passivation layers for selective growth of $GaAs_2$. In this work, formation of a thin nitrided layer is investigated. Nitrogen electron cyclotron resonance(ECR)-plasma is employed for the formation of thin nitrided layer. The plasma source used in this work is a compact ECR plasma gun3 which is specifically designed to enhance control, and to provide in-situ monitoring of plasma parameters during plasma-assisted processing. Microwave power of 100-200 W was used to excite the plasma which was emitted from an orifice of 25 rnm in diameter. The substrate were positioned 15 em away from the orifice of plasma source. Prior to nitridation is performed, the surface of n-type (001)GaAs was exposed to hydrogen plasma for 20 min at $300{\;}^{\circ}C$ in order to eliminate a native oxide formed on GaAs surface. Change from ring to streak in RHEED pattern can be obtained through the irradiation of hydrogen plasma, indicating a clean surface. Nitridation was carried out for 5-40 min at $RT-600{\;}^{\circ}C$ in a ECR plasma-assisted molecular beam epitaxy system. Typical chamber pressure was $7.5{\times}lO^{-4}$ Torr during the nitridations at $N_2$ flow rate of 10 seem.(omitted)mitted)