• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.40 no.5
• /
• pp.608-618
• /
• 1995

This study was conducted to determine physiobiochemical basis of heterosis using rice hybrids such as Shanyou 63 (Zhenshan 97As Minhui 63) and Teyou 63 (Longtepu A Minhui 63) as compared with inbred rice like Milyang 23. Seed protein patterns of rice hybrid showed complementary genetic characteristics inherited from their parents. Hybrid rice had larger embryo and higher $\alpha$-amylase activity than those of inbred rice. The larger embryo of hybrid was significantly correlated with tillering ability and high number of low node tillers jplant increased by 60~70% in Shanyou 63, leading to higher productive tillers/plant which directly influenced on grain yield of hybrid rice. These characters were further supported by high chlorophyll content in hybrids. Exogenous application of GA$_3$ (0.02 ppm) on inbred rice like Milyang 23, increased significantly $\alpha$-amylase activity, but no effect of GA$_3$ on hybrid rice was observed, indicating that sufficient amount of GA$_3$ is endogenously present in hybrid rice, showing 1 to 3.5 fold higher activity of $\alpha$-amylase in hybrid rice, which trigger heterosis from the germinating stage. Further, activity of cytochrome c oxidase was 2.66 to 5.52 fold higher in hybrid rice than that of inbred rice, indicating that rice hybrids have very active metabolism reflecting vigorous growth starting from the germinating stage, in turn leading to higher tillering ability.

• Economic and Environmental Geology
• /
• v.13 no.3
• /
• pp.167-184
• /
• 1980

The granitic plutons associated with Ogcheon geosynclinal zone can be grouped into three different subzones; SE-Subzone for the migmatitic and schistose granites of the southeast margin, 101-181m.y. old; NW-Subzone for those of the northwest margin, 112-163m. y. old; and C-Subzone for those of central part of the zone, 63-183m.y. old. The intrusives in C-Subzone are further subdivided into the older, adamellite to granodiorite (148-183m.y. old) and the younger, perthitic granites (63-106m,y. old). The metallogenic distribution of South Korea suggests that, in the Ogcheon Zone, it is possible to delineate an elongated polymetallogenic province in the general orientation of the zone intimately related with the migmatite and plutonic zones mentioned. Moreover, the mineralization in the province was basically controlled by the patterns of local geology involving country rocks and related igneous bodies, that permit subdivision of the province into the following three parts: Northeast (NE) Province consists dominantly of thick Paleozoic calcareous sediments; Middle (M) Province is characterized by predominant argillaceous and partly calcareous sediments of Precambrian to Late Paleozoic age; and Southwest (SW) Province consisting mainly of volcanic and arenaceous sediments of Mesozoic age. The three different plutonic zones with three different country rock provinces above mentioned make a combination which consists of nine classes. Each class can be assumed to be characterized by specific mineralization type. In order to classify the mineralization types, the present study sampled twenty six ore deposits and mineralized areas in Ogcheon zone as shown figure 2; eight ore deposits from plutonic SE-Subzone, ten from the plutonic NE-Subzone and eight from the plutonic C-Subzone. The characteristics of the classes are as follows: NE-SE is predominant in Au-Ag vein and Sn-migmatite of katazonal occurrence; NE-C is most productive in Pb-Zn and remarkable in Fe contact deposit in mesozone and partly Pb-Zn-Cu skarn in limestone and subordinate in mesozone and partly Pb-Zn pipes; M-SE is considerable in Au-Ag vein and rare elements (Nb, Ta, etc.) of pegmatite; M-C is predominant in F-veins in epizone and Mo-W, Fe, Cu veins occur in replacement type; M-NW is productive in Fe metamorphic and skarn types, partly remarkable in Cu, Pb-Zn contact; SW-SE is barren in mineralization related to Jurassic igneous rocks; SW-C is predominant in alunite and pyrophyllite in tuffs; and SW-NW is scarece in Pb-Zn, Cu, As and Au-Ag veins.

• Journal of The Korean Association For Science Education
• /
• v.39 no.6
• /
• pp.739-753
• /
• 2019

The purpose of this study is to explore characteristics and limitations of a novice teachers's responsive teaching practice, who framed argumentation productively. One novice teacher and two eighth-grade classes participated in this study. Two of the small student groups with active teacher intervention were selected as focus groups. Students engaged in argumentation activity where they built an argument for hearing if the eardrum was torn. We recorded the class and interviews with the teacher and the students, which were transcribed for use in the analysis of the teacher's responsive teaching practices and epistemological, positional framing. We discovered that teacher thought that he should position himself as a facilitator to encourage students to present ideas clearly and to reach consensus. His framing was consistent in responsive teaching practices. Positioning himself as a facilitator, after he framed the discussion as idea sharing discussion by eliciting and probing students' idea, he framed the discussion as argumentative discussion by taking up students' idea and pointing out disagreement between them. As a result, members of small group 1 engaged in argumentative discussion and reached consensus. However, the teacher's productive framing did not guarantee students' productive argumentation practice. In small group 2, he did not elicit and probe students' ideas successfully. As a result, members of small group 2 did not engaged in argumentative discussions. He responded limitedly to the lack of students' conceptions because of lack of understanding about learners. Also, he mainly attended to students' reasoning, and not to students' framing about argumentation because he considered argumentation only as a tool for conceptual learning. The result of this study will contribute to the establishment of responsive teaching in science classrooms.

• Journal of the Economic Geographical Society of Korea
• /
• v.13 no.3
• /
• pp.297-311
• /
• 2010

The purpose of this study is to analyze the causality among GRDP, patent, investment of R &D, and researcher among 16 Metropolitan cities and provinces in Korea. Using the annual data ranged from 1998 to 2008, the causality test for time-series data such as unit roots test and Granger causality test were performed. We estimate the Panel-Var of the four variables to find out the various Granger causal relations for two groups which are classified by the patent productivity. The panel data causality results reveal that there are bidirectional causality relations among four variables for the more patent-productivity group. The patent has bi-directional effects on GRDP and R&D. The patent cause GRDP and vice versa, patent cause R&D and vice versa. Patent not only has strong direct impact on GRDP and R&D but also has affected by the increase of GRDP and R&D through the interactive feedback mechanism. However, the causality patterns are somewhat different between the more patent-productive region and the less patent-productive region. There exists one directional causality between the R&D and GRDP for the less patent-productivity group. Such result may imply that the type of regional innovation policy should be differentiated between two groups. Regional economic policy efforts should be placed on increasing the knowledge productivity and on strengthening the regional competitiveness through the regional innovative infrastructure.

• Asian-Australasian Journal of Animal Sciences
• /
• v.17 no.12
• /
• pp.1695-1699
• /
• 2004

The antioxidant enzymes, lipid peroxidation and free radicals assessment were made of the effects of selenium, copper and magnesium on bovine endemic fluorosis under high fluoride, low selenium and low copper productive conditions. Thirty-two beef cattle were selected from high fluoride area, and randomly divided into four groups with eight cattle each as follows: (1) high fluoride control group (HFC); (2) supplemented group with 0.25 mg/kg selenium (HFSe); (3) supplemented group with 15 mg/kg copper (HFCu) and (4) supplemented group with 0.25 mg/kg selenium+15 mg/kg copper+1 mg/kg magnesium (HFSeCuMg) per day for 83 days. Moreover, eight beef cattle were selected from non-high fluoride area as normal control group. Blood samples were collected from cattle on 0 d, 30 d and 83 d respectively, to analyze the enzyme activities and concentration of GSH-px, CAT, SOD, MDA and free radicals. The results showed that the contents of free radicals and MDA in HFC group were significantly higher, and the whole blood GSH-px, CAT, erythrocyte SOD activities were lower than the normal control group. Free radicals, metabolic imbalance and antioxidant disorder therefore, play an important role in fluorosis. However, GSH-px, CAT and SOD activities in HFSe group and HFSeCuMg group at 30 d and 83 d were markedly higher than the same groups at the 0 d and the HFC group at the same time. Likewise, there was a corresponding reduction in the contents of free radicals and MDA. These findings indicated that supplementation with selenium, copper and magnesium elevated high fluoride bovine antioxidant enzymes, and decreased MDA and free radicals contents. But, the activities of supplementation selenium group did not increase until day 83. These results demonstrated that fluorosis was associated with lower serum Se and Cu levels than in the control, and it was therefore concluded that fluorosis is associated with decreased serum levels of these minerals. Long-term high fluoride intake under productive condition enhances oxidative stress in the blood, thereby disturbing the antioxidant defense of cattle. Increased oxidative stress could be one of the mediating factors in the pathogenesis of toxic manifestations of fluoride. It is benefical for high fluoride cattle supplemented with proper selenium, copper and magnesium to increase fluoride excretion and obtain the protective impact of the activity of oxidative enzymes, and to decrease lipid peroxidation and free radicals contents.

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.4
• /
• pp.588-596
• /
• 2020

Objective: The objective of this study was to investigate the effects of low doses of organic trace minerals (iron, copper, manganese, and zinc) on productive performance, egg quality, yolk and tissue mineral retention, and fecal mineral excretion of laying hens during the late laying period. Methods: A total of 405 healthy hens (HY-Line White, 50-week-old) were randomly divided into 3 treatments, with 9 replicates per treatment and 15 birds per replicate. The dietary treatments included feeding a basal diet + inorganic trace minerals at commercial levels (CON), a basal diet + inorganic trace minerals at 1/3 commercial levels (ITM), and a basal diet + proteinated trace minerals at 1/3 commercial levels (TRT). The trial lasted for 56 days. Results: Compared to CON, ITM decreased (p<0.05) egg production, daily egg mass, albumen height, eggshell strength, yolk Fe concentration, serum alkaline phosphatase activity and total protein, and increased (p<0.05) egg loss and feed to egg ratio. Whereas with productive performance, egg quality, yolk mineral retention, and serum indices there were no differences (p>0.05) between CON and TRT. The concentrations of Fe and Mn in the tissue and tibia were changed notably in ITM relative to CON and TRT. Both ITM and TRT reduced (p<0.05) fecal mineral excretion compared to CON. Conclusion: These results indicate that dietary supplementation of low-dose organic trace minerals reduced fecal mineral excretion without negatively impacting hen performance and egg quality.

• Korean Journal of Soil Science and Fertilizer
• /
• v.20 no.2
• /
• pp.185-192
• /
• 1987

A green house experiment was conducted to find out the acetylene reducing and $N_2$-fixing activity from photosynthetic and aerobic heterotrophic nitrogen fixing microorganisms in submerged paddy soil under different agricultural locality, soil series, soil texture, soil type, and drainage condition in which samples taken from without nitrogen treatment plot of NPK trials on 16 sites of the farmer's field. The results obtained were summarized as follows: 1. The highest acetylene reducing activity was observed at 7 days after incubation in the light condition (photo synthetic microbes+heterotrophic bacteria) while it was observed at 35 days incubation in the dark condition (heterotrophic bacteria). 2. Among the soil series, photosynthetic nitrogen fixing activity was pronounced more in Jangae, Ogcheon and Hwadong series while lower was obtained in Buyong and Daejeong series. Aerobic heterotrophic nitrogen fixing activity was high in Buyong and Daejong series. 3. Estimated amount of $N_2$-fixation from acetylene reducing activity was equivalented to 3.0 mg in light condition and 4.9 mg/100g/105 days in dark condition. 4. Among the agricultural locality, photosynthetic nitrogen fixing activity was high in rather warm southern part while heterotrophic nitrogen fixing activity was predominated more in mountainous area and Chungcheong continental. 5. Photosynthetic nitrogen fixing activity was predominated in high productive soil while aerobic heterotrophic nitrogen fixing activity was pronounced more in crose coarse sandy soil. 6. The soils properties of high photosynthetic nitrogen fixing activity were constituted of poorly or imperfectly drained clay or clay loam soil while heterotrophic nitrogen fixing activity was pronounced more in well to moderately well drained sandy or sandy loam soil.

• The Journal of the Korean Society for Microbiology
• /
• v.34 no.6
• /
• pp.533-542
• /
• 1999

H. pylori produces urease abundantly amounting to 6% of total protein of bacterial mass. Urease genes are composed of a cluster of 9 genes of ureC, ureD, ureA, ureB, ureI, ureE, ureF, ureG, ureH. Production of H. pylori urease in E. coli was studied with genetic cotransformation. Structural genes ureA and ureB produce urease apoprotein in E. coli but the apoprotein has no enzymatic activity. ureC and ureD do not affect urease production nor enzyme activity ureF, ureG, and ureH are essential to produce the catalytically active H. pylori urease of structural genes (ureA and ureB) in E.coli. The kinetics of activation of H. pylori urease apoprotein were examined to understand the production of active H. pylori urease. Activation of H. pylori urease apoprotein, pH dependency, reversibility of $CO_2$ binding, irreversibility of $CO_2$ and $Ni^{2+}$ incorporation, and $CO_2$ dependency of initial rate of urease activity have been observed in vitro. The intrinsic reactivity (ko) for carbamylation of urease apoprotein co expressed with accessory genes was 17-fold greater than that of urease apoprotein expressed without accessory genes. It is concluded that accessory genes function in maximizing the carbamylating deprotonated ${\varepsilon}$-amino group of Lys 219 of urease B subunit and metallocenter of urease apoprotein is supposed to be assembled by reaction of a deprotonated protein side chain with an activating $CO_2$ molecule to generate ligands that facilitate productive nickel binding.

• Journal of Plant Biology
• /
• v.35 no.4
• /
• pp.317-322
• /
• 1992

The nitrogen fixation activity and environmental factors of Lespedeza bicli!oy Turcz, forming annual root nodules by symbiotic Rhizobium sp. were analyzed in the field conditions during the growing period. Seasunal changes of $N_2-fixation$ activity showed the maximum value of $120\;\mu\textrm{M}\;C_2_H4{\cdot}noduie\;g\;fw^{-1}{\cdot}hr^{-1}$ during the active growing period (June) and varied significantly depending on the growth phase and environmental factors. The maximum activities were attained at the conditions of pH 7, $30^{\circ}C$ of temperature, 18 Kpa of oxygen partial pressure and inhibited by water stress and nitrogen sources. The habitat soil was weak acidic and poor in nitrogen, phosphorus and organic matter contents. The leaf area ratios and chlorophyll contents were ranged from 442 to $48;\textrm{cm}^2{\cdot}g\;dw^{-1}$ and from 33 to $38\;\mu\textrm{g}\;chI{\cdot}\textrm{cm}^2$. Nitrogen contents in each organ showed the maximum of 46, 19 and $11\;mg{\cdot}g\;dw^{-1}, respectively for leaf, rool and stem in the early period. The highest phosphorus contents were 4.2, 1.2 and $0.6\;mg{\cdot}g\;dw^{-1}$, respectively for leaf. root and stem in early growing period. The allocation ratios of nitrogen quantity showed 60% for leaves and 73% for roots during the active and late growth period, and 22% [or stems in average. The allocalion ralios o[ phosphorus quantity showed 58% for leaves during the most productive period, 70% for roots in the pre-growth stage and 26% for stems in average.verage.

• Korean Journal of Head & Neck Oncology
• /
• v.10 no.2
• /
• pp.200-205
• /
• 1994

Proliferating cell nuclear antgen(PCNA) plays an important role in DNA synthesis in nucleoli and is highly conserved non-histone nuclear protein composed of 261 amino acid. and is considered to correlated with the cells proliferative state, because it is synthesized particulary during the proliferative period of late Gland S-phase. Therefore, PCNA index meaningfully increases in the active or proliferative kinetic cells. By the use of recently developed monoclonal antibodies against PCNA, the immunohistochemical staining methods can make possible. These staining methods are the useful and productive one for ascertaining the cell's proliferating abillity. Moreover, immunohistochemical staining method with a antiPCNA antibody has particulrar advantages as follows. By means of these methods, we can stain the tissue that was already fixed in formalin or paraffin wax. We can see with naked eye that which cell is, where is differentiated through a microscope. Lastly, it maintains the whole tissue architecture and makes a search for the correlation. As we have seen above, the immunohistochemical staining methods for PCNA have been studied as an impotant factor that can find the cell proliferative kinetics in malignancy and biologic behavior of tumors. To investigate of the proliferative activity in thyroid nodule, Authors evaluated cell proliferative activity by immunostaing for PNCA in 45 pathologically confirmed solitary thyroid nodule. The results were as follows. 1) The benign nodules were 25 cases(Adenomatous Goiter: 20 cases, Follicular adenoma: 5 cases) and malignant nodules were 20 cases(Papillary Ca : 14 cases, Follicular Ca : 4 cases, Anaplastic Ca : 2 cases). 2) The Most prevalent age groups were 4th decade(11 cases), and the next group was 5th decade. 3) The average PCNA labelling indices were as follows. Adenomatous goiter(I6.9%), Follicular adenoma(37.6%), papillary Ca(26.3%), Follicular Ca(8.8%) and Anaplastic Ca(86.7%). There were no significant differences in benign(20.4) and malignant nodules (28.8%) except anaplastic Ca(p=0.3226). 4) When the average tumor size 2cm in papillary Ca, the PCNA indices were 26.0% (below 2cm) : 26.6% (above 2cm) (p=0.9642). The PCNA incidies were 23.9% (with lymphatic spread) : 28.7% (without lymphatic spread) (p=0.7056). There were no signlficant differences in the above cases. In conclusion, there were no significant differences in cell proliferative activity by staining for PCNA between benign and malignat nodules except anaplastic Ca.