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Empirical Research on the R&D Investment and Performance of Venture Businesses (벤처기업의 R&D 투자와 성과에 관한 실증연구)

  • Lee, D.K.;Lee, C.K.;Kim, J.H.
    • 한국벤처창업학회:학술대회논문집
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    • 2008.04a
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    • pp.179-208
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    • 2008
  • In this research, an empirical analysis was performed to determine the correlation between management performance and R&D investment for domestic venture businesses in each industry. Specifically, an empirical analysis for each industry was attempted not only to clarify the general hypothesis on the relationship between management performance and R&D investment for venture businesses but also to demonstrate that differences exist for each industry. Empirical analysis was conducted for eight industries with respect to the $2002{\sim}2006$ panel data extracted as investigative results from the "Investigation Report on Science and Technology R&D Activities" published by the Ministry of Science and Technology. Industrial classification was limited to the middle-level classification (2-digit) in the Korea Standard Industry Code (KSIC) owing to the limited number of panels. Although this research only verified the overall positive effect of R&D activities and funds for existing research on corporate value or productivity and management performance, it was able to document the difference for each individual industry and each business size unlike existing research.Furthermore, the reliability of the research results was enhanced by targeting companies that have been continuously conducting R&D and management activities using consistent 5-year panel data in the analysis. Again, this was something that existing research did not have. Finally, through the use of recent data from 2002 after the IMF economic crisis up to 2006 in the empirical analysis, this research proposed the problems due to the prevailing circumstances at the time of entering the advanced nation stage based on an empirical analysis; the prevailing problems during the pursuit of advanced nation status before the IMF crisis broke out were not tackled. The key empirical analysis yielded several results. First, capital and size of the labor force have a positive correlation with the management performance for the entire company or the venture business. This applies to all eight industries as the subjects of the analysis. Second, although the number of years since a company has been established can have positive or negative correlation with management performance for the entire company or venture business in specific industries, a definite overall trend cannot be identified. Third, R&D investment can be said to have an overall positive effect on corporate management performance. Fourth, the size of the research staff cannot be said to be a factor unilaterally affecting the management performance of the entire company or the venture business. Fifth, the number of years a research institute has been in operation, which was assumed to have a positive effect on the management performance of a company because of the accumulated R&D know-how -- definitely acts as a positive factor contributing to the management performance of a company.

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Effects of zearalenone on the localization and expression of the growth hormone receptor gene in the uteri of post-weaning piglets

  • Zhou, Min;Yang, Li Jie;Yang, Wei Ren;Huang, Li Bo;Zhou, Xue Mei;Jiang, Shu Zhen;Yang, Zai Bin
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.1
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    • pp.32-39
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    • 2018
  • Objective: In this study, we investigated the adverse effects of dietary zearalenone (ZEA) (0.5 to 1.5 mg/kg diet) on the localization and expression of the growth hormone receptor (GHR) in the uteri of post-weaning gilts and explored alternative mechanism of the reproductive toxicity of ZEA on piglets. Methods: A total of forty healthy piglets (Duroc${\times}$Landrace${\times}$Large White) aged 28 d were selected for study. Piglets were transferred to single cages after 10 days' adaptation on an obstetric table. The animals were allocated to one of four treatments: a normal basal diet supplemented with 0 (Control), 0.5 (ZEA0.5), 1.0 (ZEA1.0), or 1.5 (ZEA1.5) mg/kg purified ZEA, and fed for 35 d after the 10-d adaptation. Analyzed ZEA concentrations in the diets were 0, $0.52{\pm}0.07$, $1.04{\pm}0.03$, and $1.51{\pm}0.13mg/kg$, respectively. At the end of the feeding trial, piglets were euthanized after being fasted for 12 h. Two samples of uterine tissue from each pig were rapidly collected, one of which was stored at $-80^{\circ}C$ for analysis of the relative mRNA and protein expression of GHR, and the second was promptly fixed in Bouin's solution for immunohistochemical analysis. Results: The relative weight of the uteri and thickness of the myometrium and endometrium increased linearly (p<0.001) and quadratically (p<0.001) with an increasing level of ZEA. The results of immunohistochemical analysis indicated that GHR immunoreactive substance was mainly localizated in the cytoplasm of uterine smooth muscle, glandular epithelial, luminal epithelial, stromal, and vascular endothelial cells. In contrast, nuclear staining was rarely observed. The immunoreactive integrated optic density of GHR in the myometrium, luminal epithelium, glandular epithelium, and whole uteri of weaning gilts increased linearly (p<0.001) and quadratically (p<0.05) with an increasing level of ZEA. The mRNA and protein expression of GHR in the uteri of weaning gilts increased linearly (p<0.001) and quadratically (p<0.05) with an increasing level of ZEA. Conclusion: In conclusion, ZEA at a concentration of 0.5 mg/kg was sufficient to significantly thicken the myometrium and endometrium, and at a concentration of 1.0 mg/kg induced a high level of GHR expression to promote growth and development of the uteri. This revealed an alternative molecular mechanism whereby ZEA induces growth and development of the uteri and provides a theoretical basis for the revision of Chinese feed hygiene standards.

Quality Properties of the Refrigerated or Frozen Irradiated Beef Patty (방사선조사된 패티용 분쇄우육의 가열전 품질특성)

  • Jeon, Ki-Hong;Oh, Se-Wook;Lee, Nam-Hyouck;Kim, Yun-Ji;Park, Ki-Jae;Kim, Young-Ho
    • the MEAT Journal
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    • s.36 summer
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    • pp.72-86
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    • 2009
  • Microbial reduction, physicochemical property, and sensory evaluation of irradiated beef patty were investigated. The microbial counts of refrigerated beef patty were reduced to below the number of 3 logs after irradiation at 3 kGy. But no viable microorganism was detected in frozen beef patty irradiated at 3 kGy. Food additives such as nitrite, salt, phosphate and ascorbic acid did not affect on the inactivation of microorganism by irradiation. The irradiation effect on the water holding capacity was not significant, but frozen irradiated beef patty showed higher water holding capacity than refrigerated beef patty. The drip loss of irradiated beef patty did not show significant differences according to irradiation doses. Considering the influence of food additives, the irradiated beef patty mixed with salt and phosphate showed lower drip loss than that without food additives. In refrigerated beef patty, TBARS values were increased with increase of irradiation doses and showed lower values in the beef patty mixed with food additives than that without food additives. The redness of refrigerated beef patty showed highest values at 3 kGy of irradiation and then decreased with increasing irradiation doses, while in the frozen beef patty did not show distinct tendency according to the irradiation doses or food additives. In sensory evaluation. the irradiated beef patty showed unpleasant smell as compared with the non irradiated beef patty, but showed somewhat higher score in smell at the sample contained ascorbic acid regardless of irradiation doses.

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Effects of Selenate and Sulfate Ion Interaction in Nutrient Solution OH the Growth Of Artemisia molngotica var. tenuifolia (배양액 내의 Selenate 와 Sulfate 이온의 상호작용이 참쑥의 생육에 미치는 영향)

  • Lee, Yun-Jeong;Park, Kuen-Woo;Suh, Eun-Joo;Cheong. Jin-Cheol
    • Journal of Bio-Environment Control
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    • v.7 no.1
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    • pp.63-70
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    • 1998
  • This study was carried out to investigate the interaction of selenate and sulfate ion in nutrient solution supplyed with selenate ion. At early growth stage, the growth of Mongolian wormwood was best at 3mM sulfate ion and 2mg/$\ell$Na$_2$SeO$_4$ treatment. As they were grown and matured, at the later growth stage, the effect of antagonism between selenate and sulfate ion on the growth of each plant decreased. At supplying with selenate ion in nutrient solution, the uptake of selenate by plant had negative correlation with sulfate ion concentration in nutrient solution. The higher sulfate ion concentration, the less selenium uptake. However, the effect of antagonistic interaction of selenate and sulfate ion on the selenium uptake increased with plant age. Whereas, the uptake of sulfate ion had positive correlation with sulfate ion concentration in nutrient solution at supplying with selenate ion in nutrient solution. The uptake of sulfate ion increased with increase of sulfate ion concentration in nutrient solution. The effect of this interaction with selenate and sulfate ion increased with growth and maturity of plant. However, at 3mM sulfate ion concentration in nutrient solution, sulfate ion concentration in plant tissue decreased markedly.

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Melanogenesis Inhibitory and Antioxidant Activities of Phellinus baumii Methanol Extract (장수진흙버섯 메탄올 추출물의 멜라닌 생성 저해작용)

  • Lee, J.S.;Shin, D.B.;Lee, S.M.;Kim, S.H.;Lee, T.S.;Jung, D.C.
    • The Korean Journal of Mycology
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    • v.41 no.2
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    • pp.104-111
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    • 2013
  • Phellinus baumii is a medicinal mushroom used in Asian countries for a long period of time. The purpose of this study was to investigate the skin whitening activities of methanol extracts from fruiting bodies of P. baumii. To evaluate the antioxidant activities of the extract, polyphenol and flavonoid contents, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity and chelating activity on ferrous ions were studied. For assay of skin whitening activities, tyrosinase and DOPA inhibitory activities, and tyrosinase and melanin synthesis inhibitory activities of B16/F10 melanoma cells treated with the methanol extract were investigated. The total polyphenol content of P. baumii methanol extract was 4.19. DPPH scavenging ability of P. baumii methanol extract was 88.26% in $25{\mu}g/mL$ concentration. We tested tyrosinase inhibitory activity and melanin contents in melanoma cells. The tyrosinase activity was inhibited to 65.17% at the concentration of $125{\mu}g/mL$ and melanin synthesis was inhibited to 57.61% at the concentration of $25{\mu}g/mL$. Overall, the experimental results showed that P. baumii methanol extract had inhibitory activities of tyrosinase and melanin synthesis by dose dependent manner in B16/F10 melanoma cells. Strong ultra-violet absorption spectra in the range of 270~370 nm indicated that ethanol extract of P. baumii could protect the skin from UV. Therefore, P. baumii methanol extract might be used for development of skin whitening, anti-UV and skin care agents.

Mineralogy and Geochemistry of Quaternary Fault Gouges in the Southeastern Korean Peninsula (한반도 동남부 제4기 단층 비지의 광물학적 및 지구화학적 연구)

  • 손승완;장태우;김영규
    • Journal of the Mineralogical Society of Korea
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    • v.15 no.2
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    • pp.85-94
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    • 2002
  • XRF, XRD, EPMA have been used to investigate microstructures and mineralogical changes caused by the faulting and fluids associated with faulting in the Quaternary fault gouge zones at the Sangchon, Ipsil and Wangsan faults located at the southeastern part of the Korean Peninsula. The chemical compositions of faulted rocks and protoliths analyzed by XRF show that the fault gouges are relatively enriched in TiO$_2$, P$_2$O$_{5}$, MgO, and Fe$_2$O$_3$) compared with protoliths, indicating that the fluids associated with faulting were highly activated. XRD results show that the fault gouges predominantly consist of quartz, feldspar, calcite and clay minerals. Clay minerals formed in the gouge zones are mainly composed of smectite characterized by a dioctahedral sheet. Based on EPMA analyses various kinds of sulfide, carbonate, phosphate minerals were identified in the gouge zones and protoliths. Xenotime of grey fault gouge of the Sangchon fault and sulfide minerals of contact andesitic rock of Ipsil fault and contact grey andesitic rock of Wangsan fault were probably formed by inflow of hydrothermal solution associated with faulting prior to the Quaternary. Carbonate minerals of contact andesitic rock and gouge zone of the Ipsil fault were formed by inflow of fluid associated with faulting prior to the Quaternary. They are heavily fractured and have reaction rim on their edge, indicating that faultings and inflow of fluids were highly activated after carbonate minerals were formed. Calcites of Wangsan fault seemed to be formed in syntectonic or posttectonic Quaternary faulting.g.

Study on Comparison of Growth Performance, Feed Efficiency and Carcass Characteristics for Holstein and F1(Holstein ♀ x Hanwoo ♂) Steers and Heifers (Holstein과 교잡종 거세우 및 처녀우의 성장발육, 사료이용성 및 도체특성 비교 연구)

  • Kang, S.W.;Oh, Y.K.;Kim, K.H.;Choi, C.W.;Son, Y.S.
    • Journal of Animal Science and Technology
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    • v.47 no.4
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    • pp.593-606
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    • 2005
  • Present study was conducted to investigate the optimal feeding levels for producing the high quality meat on the basis of the information deriving from the comparison of the growth performance and carcass characteristics among breeds(Holstein vs F1, Holstein♀×Hanwoo♂), sex(steer vs heifer) and interaction between breed and sex. Thirty two animals on 4 treatments(i.e. eight head each) were used for 540 days from seven to 24 months of age. The results obtained are summarized as follows; the range of average daily gains was 0.733 to 1.018, 0.994 to 1.255, 0.947 to 1.259 and 0.736 to 0.824kg for the growing, the early-fattening, the mid- fattening and the finishing periods, respectively. The range of average daily gains for the entire period was 0.882 to 1.061kg. The gains were higher for Holstein(7.3%) and the steers(10.5%) than F1 and the heifers, respectively. Concentrates and total digestible nutrients intakes per kg gain were higher for Holstein and the heifers than F1 and the steers, respectively. These findings may indicate that feed utilization is higher for Holstein than F1, and higher for the steers than the heifers. In carcass characteristics, back fat thickness was thicker for Holstein than F1, and rib-eye area was smaller for Holstein than F1. The rib-eye area per kg carcass weight was larger for F1 and the heifers than Holstein and the steers, respectively. Meat color was better for Holstein than F1, but the sex distinction did not show any differences. In physicochemical properties of longissimus dorsi, shear force, cooking loss, water holding capacity and the panel test scores of juiciness, tenderness and flavor for F1 and the heifers were better than those for Holstein and the steers, respectively. According to the above results, we may conclude that F1 and heifers rather than Holstein and steers are recommended for high quality meat production. In steers and heifers of Holstein and F1, the optimal feeding levels may be 1.9% of apparent body weight for concentrates and 25% of concentrates intake for rice straw.

Effect of Feeding High Guality Hay on Performance and Physico-chemical Characteristics of Carcass of Hanwoo Steers (양질의 건초 급여가 한우 거세우의 비육성적 및 도체의 이화학적 특성에 미치는 영향)

  • Kim, S.I.;Jung, K.K.;Kim, J.Y.;Lee, S.W.;Baek, K.H.;Choi, C.B.
    • Journal of Animal Science and Technology
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    • v.49 no.6
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    • pp.783-800
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    • 2007
  • The current study was conducted to investigate the effect of high quality hay on the performance and carcass characteristics of Hanwoo steers. Twenty(20) Hanwoo(7 months old) were allocated into either Control(rice straw fed) or Treatment(timothy hay and rice straw fed) group(10 animals per group) and fed for 710 days until the animals reached at 30 months old. Concentrates were fed according to the feeding program composed with three(3) phases; growing, fattening, and finishing period. For the overall feeding period, final body weights were 761.3 and 799.6kg for the Control and Treatment groups, respectively, showing 38.3kg heavier body weight in Treatment group. ADG were 0.79 and 0.84kg for Control Treatment groups, respectively. These results might be because of the intake of high quality hay during growing phase and the effects persisted until the end of the experiment. Feed intake tended to be higher in Treatment group whereas feed conversion did not show significant difference between groups. Cold carcass weights were 451.0 and 475.3kg for Control and Treatment, There were no significant difference between groups in both yield and quality grade. There were no remarkable differences in physico-chemical characteristics fatty acid composition of carcasses between groups. In conclusion, it would be beneficial to feed high quality hay such as timothy during growing period of Hanwoo steers to produce high quality beef with heavier live and carcass weight.

Inverse Agonists at $A_1$ Adenosine Receptors in Rat Cerebral Cortex (흰쥐의 뇌의$A_1$ 아데노신 수용체에 작용하는 역효현제에 관한 연구)

  • Park, Kyung-Sun;Yang, Wan-Suk;Kim, Kyung-Hwan
    • The Korean Journal of Pharmacology
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    • v.32 no.1
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    • pp.23-29
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    • 1996
  • According to the traditional receptor model, competitive antagonists share with agonists the ability to bind to a common site on receptors, but they are different from agonist in that they cannot trigger the biological response-i.e., they lack intrinsic efficacy. Recent findings extend the model by indicating that not all antagonists display an intrinsic efficacy of zero but that some display 'inverse agonism'. In the present study we studied the inverse agonism at $A_1$ adenosine receptors in membranes prepared from rat cerebral cortex. Eight commercially available $A_1$ adenosine receptor antagonists (CGS-15943, ADPX, CPT, DPCPX, DPX, N-0840, PACPX and 8-PT) were screened for inverse agonism by measuring the extent of $[^{35}S]guanosine-5'-({\gamma}-thio)$ triphosphate $([^{35}S]GTP_{\gamma}S)$ binding to G proteins. The agonist-induced stimulation of $[^{35}S]GTP_{\gamma}S$ bindings was completely blocked in the presence of $A_1$ adenosine receptor antagonists. Under optimal conditions, two types of antagonists could be distinguished. Seven antagonists including DPCPX decreased the basal $[^{35}S]GTP_{\gamma}S$ binding in the absence of agonist, displaying inverse agonist activity. One (CGS-15943) had no effect on the basal bindings. N-ethylmaleimide treatment reduced the basal bindings as well as agonist-mediated stimulation of $[^{35}S]GTP_{\gamma}S$ bindings, indicating that a substantial amount of this binding reflects an activated state of the C proteins. In good agreement with these findings, 0.1 mM GTP decreased the apparent affinity of the receptors for the agonist PIA, increased that for DPCPX, and had no effect on that for CGS-15943.

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Effect of Dietary Betaine and Energy Levels on Liver Fats and Cholesterol in Laying Hens (사료내 비태인과 에너지 수준이 산란계의 간지방과 콜레스테롤에 미치는 영향)

  • Park J. H.;Park S. Y.;Ryu K. S.
    • Korean Journal of Poultry Science
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    • v.32 no.3
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    • pp.149-156
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    • 2005
  • Two experiments were conducted to examine the effects of betaine intake on blood and yolk cholesterol, abdominal fat, liver fat, tissue triglyceride(TG) and liver HMG-CoA reductase In laying hens. In Expt. 1, a total of 72 ISA-brown laying hens were individually assigned into four treatments from 18 to 21 weeks old. Com-soybean meal based diet were fed with the addition of 0, 300, 600 and 1,200ppm. In Expt. 2, 72 ISA-brown laying hens were housed into individual cage to evaluate the effect of dietary betaine(0, 600ppm) and energy(ME, 2,800, 2,900kca/kg) from 70 to 74 weeks. Serum total cholesterol, LDL and HDL-cholesterol and TG concentration in blood of hens fed betaine tended to increase compared to those of the control, but were not significantly different. However, betaine supplementation showed a statistically significant decrease in yolk cholesterol(P<0.05). There was no significant difference in abdominal fat among the treatments. Liver fats and 7c of birds 130 betaine was decreased compared with control. Serum total cholesterol, LDL-cholesterol and triglyceride concentration were significantly inc.eased by ffeding a diet containing 600ppm betaine in Expt. 2(P<0.05), but were not influenced by the dietary energy levels. Yolk cholesterol, abdominal fat and HMG-CoA reductase activity were affected neither by dietary energy nor betaine level.