• Korean Journal of Poultry Science
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• v.44 no.4
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• pp.259-265
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• 2017

This study was to investigate the effect of chick weight in the early growth period on market-weight of Korean native chickens (KNCs). We measured the body weights of 1,087 chickens (male 479, female 608) of 13 KNC strains at 1-84 days of age at two week intervals. The growth performance of the 13 KNC strains was investigated. Correlation coefficients among the weights of chickens in each growth period and regression of market-weight on early chick weights were analyzed. The results showed that the average body weight of 70-day-old KNCs was 1,962g: 2,154g and 1,819.7g for males and females, respectively. The equation for regression of body weight on age was estimated as $\hat{Y}=0.1347X^2+18.738X-40.134$ ($R^2=0.9418$). Using this regression equation, the duration required to attain a KNC market-weight of 2 kg was estimated as 71.8 days. All the correlation coefficients between early chick weight and market-weight were significantly positive. Although the correlation coefficients among the chick weights in each growth period decreased with increase in age interval, early growth weight had a significant effect on late growth performance. The correlation coefficient between market-weight at 70-days and chick weight at 1-day was estimated to be a low as 0.10-0.13. In the estimations of market-weight correlation coefficients, correlation coefficient and coefficient of determination were high in the female and male chicks after 28-days and 42-days of age, respectively. The results of the analysis of correlation and regression between early chick weight and market-weight of KNCs showed that market-weight could be predicted based on the weights of 28-day-old females and 42-day-old males.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.1
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• pp.33-46
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• 2017

In Korea, small and medium sized domestic enterprises (SMEs) play an pivotal role in the national economy, accounting for 99.8% of all enterprises, 87.9% of total employment, and 48.3% of production. and SMEs were driving a real force of the development of national economy in many respects such as innovation, job creation, industrial diversity, balanced regional development. Despite their crucial role in the national development, most of SMEs suffer from a lack of R&D capabilities and equipments as well as funding capacity. Government-Supported Research Institute (GRI) can provide SMEs with valuable supplementary technological knowledges and help them build technological capacities. so, In order to effectively support SMEs, government and GRI must be a priority to know about the factors influencing the performance related to technology transfer and technological collaborations. The paper analyzes the effects of Korean IT SMEs Venture external collaborations and technology transfer on their performances, according to their collaboration activities and technology transfer experiences. The results show that there was a significant difference between '3~5times' of technology transfer experience and 'zero technology transfer experience' in the case of technology transfer experience. In case of technological collaboration type, there was a significant difference between 'R&D manpower' and 'enhancement of technological capabilities including core technologies'. The results show that the effectiveness of technology transfer of Korean IT SMEs Venture depends on experiences, types of collaboration activities. so the results of this research will be useful for Government-Supported research institute (GRI)' policy makers when establishing technology commercialization support policies and strategic planning of small and medium sized domestic enterprises.

• Pediatric Infection and Vaccine
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• v.20 no.2
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• pp.53-62
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• 2013

Purpose: The cross-protection of 7-valent pneumococcal conjugate vaccine (PCV7) against vaccine-related serotypes has been controversial. We investigated the serological properties of cross-protective antibodies against vaccine-related serotypes 6A, 6C, and 19A induced in young children aged 12-23 months after booster immunization of PCV7. Methods: IgG and IgM antibody concentrations and opsonic index (OI) against vaccine serotypes 6B and 19F and vaccine-related serotypes 6A, 6C, and 19A were measured by ELISA and opsonophagocytic killing assay (OPA) in 4 selected immunesera. The serological properties and antigenic specificity of protective antibodies were determined by IgM depletion of immunesera, OPA, and competitive OPA against serogroup 6 and 19 pneumococci. Results: Compared to pre-IgM depleted immunesera, OI of IgM-depleted immunesera against 6B and 19F decreased and OI against 6A, 6C, and 19A decreased, too. In competition OPA, free 6B and 19F polysaccharide completely inhibited the immune protection against vaccine-related serotypes 6A, 6C, and 19A as well as vaccine types 6B and 19F. Conclusions: The booster immunization of PCV7 certainly induced cross-protective antibodies against vaccine-related serotypes 6A, 6C, and 19A with both IgG and IgM isotypes. Furthermore, IgM antibodies are more highly contributed to opsonophagocytic activity against vaccine-related serotypes as well as most of vaccine types than do IgG antibodies. Further studies are needed for the more immunized sera in the children as well as adults.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.2
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• pp.74-82
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• 2004

This study was conducted to estimate the optimum application rate of fertilizer N based on $NO_3-N$ concentration in soils for tomato (Lycopersicon esculentum Mill.) cultivation in plastic film house. Tomato plants were cultivated with and without fertilizer in twelve soils which have different concentrations of $NO_3-N$ ranging from 46 to $344mg\;kg^{-1}$. Dry weight (DW) of above-ground part of tomato with no fertilizer ranged from 28.9 to $112.5g\;plant^{-1}$, depending on N-supplying capability of soils. The soil $NO_3-N$ was positively correlated with DW ($r=0.83^{**}$) and N uptake ($r=0.78^{**}$) by tomatoes in no fertilizer treatment, and negatively correlated with fertilizer effciencies resulted from the differences of DW and N uptake between fertilized and non-fertilized plot. The relationships between soil $NO_3-N$ concentration and DW, N uptake, and fertilizer efficiency were analyzed to determine the critical levels of soil $NO_3-N$ for tomato cultivation. The limit critical levels of soil $NO_3-N$ were estimated to be more than $280mg\;kg^{-1}$ for no application of fertilizer N and to be less than $50mg\;kg^{-1}$ for recommended application of fertilizer N. These critical levels of soil $NO_3-N$ were nearly the same as those calculated from regression equation between electrical conductivity(EC) and soil nitrate for critical levels of EC in recommendation equation of fertilizer N for tomato under the plastic film house by NationaI Institute of Agricultural Science and Technology. Consequently, the optimal application rate of ferdilizer N for tomato cultivation in the soils containing $NO_3-N$ concentration between $280mg\;kg^{-1}$ and $50mg\;kg^{-1}$ was estimated by the equation Y = -0.4348X＋121.74, where Y is the percent(%) to the recommended application rate of N fertilizer and X is the soil $NO_3-N$ concentration ($mg\;kg^{-1}$).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.4
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• pp.361-371
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• 1992

For the increase of grain yield potential in rice, a low-tillering large panicled type has been suggested as an ideotype. A low-tillering plant type may have different yield potential and needs different cultural practices from that used in a high-tillering type for the maximum yield. This study was conducted to evaluate the grain yield performances of a low-tillering large panicled rice and high-tillering small panicled rice at different plant spacings, nitrogen(N) levels and seedling numbers per hill. A low-tillering large panicled genotype, IR25588 was compared with a high-tillering small panicled IR58. The grain yield of IR25588 was significantly higher than that of IR58 under a narrow spacing with high N level. The maximum yields of IR58 and IR25588 were reached at about 35,000 and 40,000 spikelets per m$^2$, respectively. The increased grain yield in IR25588 was mainly due to the increase in spikelet number per unit area which is the most precise indicator of grain yield in rice. The optimum spacing for the maximum yield was denser for IR25588 than that for IR58 under high N level. The intra-hill competition of the low-tillering type was lower than that of the high-tillering type. The higher dry matter production and bigger leaf area and culm weight were the main factors for increased grain yield in a low-tillering panicle weight type. Based on the results, the yield potential of a low-tillering panicle weight type was higher than that of a high-tillering panicle number type, especially under a close spacing with high N level.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.3
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• pp.199-212
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• 2007

If a type IP-2 transport package were to be subjected to a free drop test and a penetration test under the normal conditions of transport, it should prevent a loss or dispersal of the radioactive contents and a more than 20% increase in the maximum radiation level at any external surface of the package. In this paper, we suggested the analytic method to evaluate the structural safety of a type IP-2 transport package using a thick steel plate for a structure part and a bolt for tying a bolt. Using an analysis a loss or dispersal of the radioactive contents and a loss of shielding integrity were confirmed for two kinds of type IP-2 transport packages to transport radioactive waste drums from a waste facility to a temporary storage site in a nuclear power plant. Under the free drop condition the maximum average stress at the bolts and the maximum opening displacement of a lid were compared with the tensile stress of a bolt and the steps in a lid, which were made to avoid a streaming radiation in the shielding path, to evaluate a loss or dispersal of radioactive waste contents. Also a loss of shielding integrity was evaluated using the maximum decrease in a shielding thickness. To verify the impact dynamic analysis for free drop test condition and evaluate experimentally the safety of two kinds of type IP-2 transport packages, free drop tests were conducted with various drop directions. For the tests we examined the failure of bolts and the deformation of flange to evaluate a loss or dispersal of radioactive material and measured the shielding thickness using a ultrasonic thickness gauge to assess a loss of shielding integrity. The strains and accelerations acquired from tests were compared with those by analyses to verify the impact dynamic analysis. The analytic results were larger than the those of test so that the analysis showed the conservative results. Finally, we evaluated the safety of the type IP-2 transport package under the stacking test condition using a finite element analysis. Under the stacking test condition, the maximum Tresca stress of the shielding material was 1/3 of the yielding stress. Two kinds of a type IP-2 transport package were safe for the free drop test condition and the stacking test condition.

• Reproductive and Developmental Biology
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• v.36 no.3
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• pp.147-154
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• 2012

This study was designed to determine whether low-density lipoproteins (LDL) from egg yolk and taurine, hypotaurine and trehalose as antioxidant in extender improve the freezability and fertility of Korean Jeju Black Bull semen. The semen was cryopreserved with tris egg yolk extenders containing 7% glycerol and treated 4% LDL, 20 mM taurine, hypotaurine and trehalose. Frozen-thawed sperm were evaluated motility, viability, membrane, and acrosome integrity and sperm penetration ability. The results were compared to semen cryopreserved in tris egg yolk extender only as control. Frozen-thawed semen evaluation cleary indicated that the addition of LDL and LDL-antioxidants (taurine, hypotaurine and trehalose) combination were significantly improved (p<0.05) the viability (%; with staining test using eosin-Y) compared to control spermatozoa. Also, in membrane integrity (%; with supravital hypo-osmotic swelling test), not only LDL-antioxiants combination but also LDL were significantly increased (p<0.05) the swelled sperm using HOST compared to control. Sperm acrosome integrity state was classified by CTC (chlortetracycline) staining test. F pattern was significantly increased in LDL-antioxidant combination than control (p<0.05) and B pattern was not significantly differences among all treatments and control. However, AR pattern was significantly decreased in LDL-antioxidants combination than control (p<0.05). Pronucleus formation and sperm penetration index (SFI) were significantly increased in LDL and LDL-antioxidants combination than control (p<0.05). Especially, LDL-taurine significantly improved pronucleus fomation and SFI than LDL (p<0.05). It was concluded that LDL and LDL-antioxidants in extender improved the freezability and fertility of Korean Jeju Black bull spermatozoa.

• Reproductive and Developmental Biology
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• v.35 no.3
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• pp.247-250
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• 2011

The objective of this study was to find out candidate genes associated with litter size trait in pigs of inbred Large Yorkshire and Landrace populations. 86 sows were screened for candidate genotypes along with litter size data recordings. Association of litter size with genotypes of candidate genes were investigated to verify the usefulness of each gene's genotypes as markers for the trait. For the lines of Large Yorkshire, PRLR3 and RBP4 genes were genotyped. Frequency distribution of PRLR3 with genotypes AA, AB and BB were each 0.14, 0.44 and 0.42. And the average litter size by PRLR3 genotypes were 8.83, 10.81 and 10.70 piglets per litter, the average estimated breeding values of which were 0.243, 0.332, 0.365, respectively for AA, AB and BB genotypes. Genotypic frequencies of RBP4 by AA, AB and BB genotypes were 0.10, 0.44 and 0.46. The average litter size by genotypes of RBP4 were 10.40, 10.57 and 10.35 piglets per litter and their corresponding average estimated breeding values were 0.451, 0.353 and 0.261, respectively for genotypes AA, AB and BB. Significance in differences among genotypes were not observed, but B allele of RBP4 seems to be associated with litter size. In Landrace lines, frequencies of RBP4 genotypes, AA, AB and BB were 0.29, 0.55 and 0.16. And the average litter size of these genotypes were 10.50, 11.08 and 11.00 piglets per litter. The corresponding averages of estimated breeding values of each genotypes were 0.172, 0.135 and 0.104. In Landrace lines, allele A was more likely to be associated with litter size, even if differences among average litter size were not significant. We conclude that genotyping of two candidate genes is a helpful tool to identify genetic potentials of litter size in pigs.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.585-592
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• 2003

The current study was conducted to determine the relationships of vitamin A on meat quality of Hanwoo as a basic study to manipulate vitamin A contents in feeds to produce high quality beef. Concentrations of vitamin A in serum and liver of Hanwoo steers(n=328) were analyzed and correlation coefficients with carcass properties were evaluated. Mean vitamin A concentration in the serum of Hanwoo steers in the early fattening period was 212.0$\pm$32.7 IU/dl, and that in the late fattening period was 117.56$\pm$43.15 IU/dl. Mean vitamin A concentration in the liver of Hanwoo steers in the late fattening period was 143.62$\pm$110 IU/g expressing large variations might be depended on animals, feeds and farms. There were negative correlations between serum vitamin A concentration and marbling degree(r=-0.24, P<0.01), fat contents in M. Logissimus dorsi (r=-0.21, P<0.01), and beef quality grade(r=-0.20, P<0.01). Vitamin A-palmitate in liver also expressed negative correlations with fat contents in M. Logissimus dorsi (r=-0.18, P<0.01) and beef quality grade(r=-0.16, P<0.05). From the results obtained in the current study, we concluded that it might be possible to produce high quality beef in Hanwoo by manipulating vitamin A contents in the feeds. Further detailed studies, however, are necessary to determine vitamin A contents in feeds, feeding levels, and feeding periods.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.543-550
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• 2003

Two experiments were conducted to determine the effects of deletion of vitamin and trace mineral premixes on growth, feed efficiency, backfat thickness, hemoglobin content, muscle vitamin E content, and fecal, serum and muscle trace mineral contents in finishing pigs raised under two different housing conditions. In Exp. 1, three pens (or experimental units) of five pigs each (average weight $\pm$ s.e., 70 $\pm$ 0.5 kg) were assigned to a control diet (with vitamin and trace mineral premixes) or diets with 50 or 100% of the premixes deleted. Pigs were fed to market weight under sub-optimal housing conditions with sawdust-covered concrete floor and no electrical ventilation. In Exp. 2, three pens of four pigs each (average weight $\pm$ s.e., 56 $\pm$ 1.1 kg) were assigned to a control (with vitamin and trace mineral premixes), Diet-P (100% of the premixes deleted) or Diet-P+E (Diet-P plus 100 mg $\alpha$-tocopherol acetate/kg diet fed for the last 2 wk before slaughter). Pigs were fed to market weight under optimal housing conditions with 70%-slatted concrete floor, electrical ventilation and temperature control. No significant differences were found in average daily gain (ADG), average daily feed intake (ADFI), and gain/feed among treatments in both experiments, but in Exp. 2 done with younger pigs, ADG and ADFI tended to be higher in the control group than in pigs fed diet without premixes. Hemoglobin content, hematocrit and red blood cell count were not influenced by the deletion of premixes. Backfat thickness was not different among treatments. Fecal Mn (twofold) and Zn (threefold) contents were higher in the control than in pigs fed diets without the premixes. Serum trace mineral contents were not influenced by diets. $\alpha$-Tocopherol content in gluteus maxima was decreased (P< 0.01) by deleting the dietary premixes, but increased to the level higher than the control by adding 100 mg $\alpha$-tocopheryl acetate/kg diet fed for the last 2 wk before slaughter. Results indicate that: 1) supplementary vitamins and trace minerals may not be necessary for optimum growth in finishing pigs, and 2) deletion of the dietary premixes reduces muscle vitamin E content, but the reduced content can be reversed by adding $\alpha$- tocopherol to diets fed for the last 2 wk before slaughter. The deletion may help to alleviate the environmental load of certain minerals from manure.