• Title/Summary/Keyword: Cell-centered

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Prospect on the Fixation of $F_1$ Hybrid Seed by Means of 2n Apomixis (2n性 單爲생殖 이용에 의한 固定 $F_1$種子 생산과 그 展望)

  • 한창열;한지학
    • Korean Journal of Plant Tissue Culture
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    • v.24 no.4
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    • pp.239-256
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    • 1997
  • Plants belonging to the category of 2n apomixis or agamospermy form embryos and seeds without the processes of normal meiosis and syngamy. Seeds produced in this way have identical genotype of their maternal parent. Three different types of agamospermy are recognized: diplospory, apospory, and adventitious (adventive) embryony. $F_1$ hybrid cultivars cannot be used as seed sources in the next ($F_2$) generation because this generation would be extremely variable as a result of genetic segregation. Hybrid vigor is also reduced in the $F_2$ generation. Therefore, parental stocks for hybrid seed production need to be maintained and cross must be continuously repeated. Agamospermic 2n apomixis would make it possible to fix the genotype of a superior variety so that clonal seeds faithfully representing that genotype could be continuously and cheaply produced independent of pollination. That is, $F_1$ hybrid seeds could be produced for many generations without loss of vigor or genotype alteration. Production of apomictic $F_1$ hybrid seed would be simplified because line isolation would not be necessary to produce seed or to maintain parental lines, and the use of male-sterile lines could be avoided. Overall, apomixis would enable a significant reduction in hybrid seed production costs. Additionally, the production of clonal seed is not only important for seed propagated crops, but also for the propagation of heterozygous fruit trees and timbers. Clonal seed would help avoid costly and time-consuming vegetative propagating methods that are currently used to ensure the large-scale production of these plants. Apomixis is scattered throughout the plant kingdom, but few important agricultural crops possess this trait Therefore, most research to date has centered on introgressing the trait of apomixis into agricultural crops such as wheat, maize, and some forage grasses from wild distant relatives by traditional cross breeding. The classical breeding approach, however is slow and often impeded by many breeding barriers. These problems could be surmounted by taking mutagenesis or molecular approach. Arabidopsis thaliana is a tiny sexually reproducing plant and is convenient in constructing and screening in molecular researches. Male-sterile mutants of Arabidopsis are particularly suitable genetic background for mutagenesis and screening for apomictic mutants. Molecular approaches towards isolating the genes controlling the apomictic process are feasible. Direct isolation of genes conferring apomixis development would greatly facilitate the transfer of this trait to wide variety of crops. Such studies are now in progress.

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Optimum Conditions for Growing Gem-quality Colorless Cubic Zirconia (보석용 무색 큐빅 저코니아의 최적 육성 조건)

  • 김원사;유영문;신현숙
    • Journal of the Mineralogical Society of Korea
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    • v.14 no.2
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    • pp.99-110
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    • 2001
  • A gem-quality yttria-stabilized zirconium oxide crystals were synthesized by the skull-melting method, using the RF electrical apparatus. Principal raw materials used were $ZrO_2$and 25 wt.% $Y_2O_3$as stabilizer and 0.03~0.05 wt.% $Nd_2O_3$decolorizing agent were added to it. The single crystals were approximately 20$\times$63 mm in size with chemical composition $Zr_{0.73}$ $Y_{0.27}$ $O_{1.87}$ . The crystals are isotropic with no appreciable anisotropism under a polarizing microscope. Their refractive indices are in the range of 2.15~2.18, specific gravity 5.85, Mohs' hardness 8~8.5, and reflectivity 13.47%. The zirconia crystals were confirmed to have cubic structure with Face-centered lattice(Z=4), space group Fm3m ($CaF_2$-type structure) and unit cell parameters are a=5.157 $\AA$. The optimal growing conditions for yttria-stabilized zirconia are 50 kW, 2.94 MHz in power and to use a crucible with 105 mm $\times$ 135 mm in size. When the lowering speed of the crucible was set 16mm/hr gave the best yield, 42%. Since the refractive index(2.15~2.18) of cubic zirconia is smaller than that of diamond, the angle between crown and pavilion should be fashioned to make it smaller than $40.5^{\circ}$ to show the maximum brilliancy and fire.

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A Development of Green Transportation Design for Special Identity of Jecheon Area - centered on Exterior Design for Development of Design Business - (제천지역의 특성화를 위한 친환경운송수단 디자인개발 - 디자인비즈니스 개발을 위한 익스테리어 디자인을 중심으로 -)

  • Mun Keum-Hi
    • Archives of design research
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    • v.19 no.4 s.66
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    • pp.175-186
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    • 2006
  • In the 21C, each nation controls exhaust fumes from automobiles and makes an effort to develop alternative energy because of serious environmental problem. Jechon area has many historical and cultural archeological sites. And Jechon city sponsors various cultural events. But the way of transportation which is connected with Jecheon and around sightseeing places is general and not ready yet. Therefore, if a special means of vehicle is developed, it could play an another role of sightseeing resources. Special identity of Jecheon area for establishment of green vehicle traffic system which gives Jecheon area specific character was investigated for theoretical background. Traffic system was studied for establishment of direction through existent successful case study. Moreover content, method, structure and advantage & shortcoming etc. of vehicle that use green energy resource such as solar car, fuel cell car, hybrid car, natural gas car etc. were examined. The suitable means of vehicle for Jechon area was proposed to three directions with research and investigation. After comparison and investigation by inquiry of each section's experts, the most suitable traffic system of which energy resource of car, form of vehicles, the complement, dimension of vehicles etc. were decided. Design proposal should be drawn according to process of automobile design in decided direction. Special Exterior design of vehicle that use green energy resource connecting Jecheon and around area should be suggested in Jecheon City Hall and Chungchong-bukdo provincial office for vivify image of cleanliness area.

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A Study on Narrative in Louise Bourgeois' "You Better Grow Up" (루이즈 부르주아의 작품 의 내러티브 분석)

  • Oh, Sang-Il
    • Journal of Science of Art and Design
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    • v.9
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    • pp.49-87
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    • 2006
  • Narrative has broad domains. So it is related to the everything man faces in his daily life and also performed in various modes. Narrative is revealed through all media including a character, which is also applied to plastic art. And narrative objects formed beyond the differences in media aid forms of expression are commonly based on a language. The study on such objects which created a new conceit of narratology can be said to be a spiritual trend by which to understand the world and man from the viewpoint of a 'story'. Plastic art took high interest in narrative in the same period as the rise of postmodernist art in the latter half of the 20th century, which was also applied to sculpture. The researcher, therefore, investigated through the history of sculpture in the 20th century the process in which narrative was denied under the value system of modernism and reappeared with the quickening of postmodernism. And as a result this period could be briefly characterized by 'return to figure' and 'reappearance of narrative'. The is, such flow means that late sculpture converted its center of interest from simple geometric abstract forms to irregular, figurative images. The researcher chose as the subject of his study the work of Louise Bourgeois, who was judged to have performed narrative positively and successfully among a great number of performed narrative positively and successfully among a great number of postmodernist sculptors who adopted it as their own strategy of expression. As the central artist of postmodrnist sculpture, She expressed human desire and condition as sexuality through the introspection of her own personal experience in contrast to the character of pop art sensitive to external world. The researcher borrowed narrative semiotics as a method of analyzing more elaborately the problem about the generation of narrative shown in her works. For it, he selected as the sample work for analysis Bourgeois's , which were judged to contain narrative most abundantly and as the metaphor of a gaze and recollection presented a new woman self that sublimed love, hatred, and loneliness. The narrative in her works are characterized by introspection questioning one's own trauma. It has independent domain and characteristics and clearly reveals narrative and content-centered characteristics, which are commonly discovered in postmodernist sculpture. The researcher could more concretely and definitely understand the characteristics of narrative through figurative images by analyzing the sample work. The researcher wanted to call your attention to the fact that the sculpture in the late 20th century contained narrative commonly and uniformly despite being characterized by various expressions and modes. And the focused on highlighting the fact that the narrative was more effectively revealed through figurative images of human body and simultaneously analyzing the formalizing process and structure for narrative. Besides he wanted to argue that the position of narrative defining the characteristics of sculpture should be valued more justly. Also, such acceptance of narrative, which is discovered in the sculpture, will have to be understood as the characteristics of the period reflecting the cultural aspect of the present time.

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A Review of Experimental study on Dementia in Oriental medicine;within Oriental medicine journal since 2000 (치매에 대한 최신 실험적 연구 동향;2000년 이후 한의학 학술지를 중심으로)

  • Choi, Sung-Youl;Kim, Dae-Hyun;Kim, Sang-Tae;Kim, Tae-Heon;Kang, Hyung-Won;Lyu, Yeong-Su
    • Journal of Oriental Neuropsychiatry
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    • v.19 no.1
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    • pp.125-146
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    • 2008
  • Objectives : The purpose of this study is to suggest for the following experimental study of dementia by reviewing recent oriental medicine journals that have been published since 2000. Methods: We have investigated various types of studies in relation to dementia through 90 articles that have been published from 2000 to 2007 in recent oriental medicine journals were registered Korea research foundation. Results and Conclusions : 1. Since 2000, 88 articles in relation to dementia have been published and almost of them are herbal medicine-centered studies. Also they show a tendency to increase every year. The journal of oriental neuropsychiatry carries the highest number of studies in relation to dementia. 2. According to the experimental paper, there are 30 cases of using herb simplexes, 48 cases of herb-combined prescription, and 10 cases of other ways. Especially 7 cases of using herb-combined prescription relation to Sasang constitution are all for the Taeumin. 3. There are 85 cases of Animal and cellular experimental, 60 cases of using pathologic model induced cytotoxic activity, a case of using L-NAME, 3 cases of 192 saporin, 4 cases of ibotenic acid, 10 cases of focal cerebral ischemia, 3 cases of alcohol-administered, and one case of natural degradation. 4. Moms water maze, Radial arm maze Passive avoidance learning model were using for examining learning and memory of model animal 5. We propose that following studies of dementia are to he investigated of the applied method of using siRNA with tranceduced gene, sample preparation by water-soaking, oriental medical diagnosis, standardization of differentiating symptom and herb simplexes, building the database by classified prescriptions, and experiment model which are based on precise examining mechanism with cell line as like mouse H19-7 hippocampus, rat HT22 hippocampus, astrocyte, microglia, using the model of animals at APP, PS1, BACE, CT99/PS1, APOE4, Tau, APP/PSI/Tau

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Biosynthesis of Silver Nanoparticles Using Microorganism (미생물을 이용한 은 나노입자 생합성)

  • Yoo, Ji-Yeon;Jang, Eun-Young;Hong, Chang-Oh;Kim, Keun-Ki;Park, Hyean-Cheal;Lee, Sang-Mong;Kim, Young-Gyun;Son, Hong-Joo
    • Journal of Life Science
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    • v.28 no.11
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    • pp.1354-1360
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    • 2018
  • The aim of this study was to develop a simple, environmentally friendly synthesis of silver nanoparticles (SNPs) without the use of chemical reducing agents by exploiting the extracellular synthesis of SNPs in a culture supernatant of Bacillus thuringiensis CH3. Addition of 5 mM $AgNO_3$ to the culture supernatant at a ratio of 1:1 caused a change in the maximum absorbance at 418 nm corresponding to the surface plasmon resonance of the SNPs. Synthesis of SNPs occurred within 8 hr and reached a maximum at 40-48 hr. The structural characteristics of the synthesized SNPs were investigated by various instrumental analysis. FESEM observations showed the formation of well-dispersed spherical SNPs, and the presence of silver was confirmed by EDS analysis. The X-ray diffraction spectrum indicated that the SNPs had a face-centered cubic crystal lattice. The average SNP size, calculated using DLS, was about 51.3 nm and ranged from 19 to 110 nm. The synthesized SNPs exhibited a broad spectrum of antimicrobial activity against a variety of pathogenic Gram-positive and Gram-negative bacteria and yeasts. The highest antimicrobial activity was observed against C. albicans, a human pathogenic yeast. The FESEM observations determined that the antimicrobial activity of the SNPs was due to destruction of the cell surface, cytoplasmic leakage, and finally cell lysis. This study suggests that B. thuringiensis CH3 is a potential candidate for efficient synthesis of SNPs, and that these SNPs have potential uses in a variety of pharmaceutical applications.

Characteristics of User's Behavior across Generations for space planing in General Hospital (종합병원 환경계획을 위한 세대별 종합병원 이용행태 특성분석)

  • Park, Hey Kyung;Oh, Ji Young
    • Korea Science and Art Forum
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    • v.28
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    • pp.105-116
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    • 2017
  • This study is a basic research to suggest user-centered general hospital environmental design guidelines, which aims to analyze user's behavior characteristics across generation in general hospital. For this purpose, this study constructed an analysis tool through the literature review with regard to generation and behavior characteristics in general hospital. Besides, an online survey regarding user's behavior in general hospital was conducted targeting from 20s to 60s, 300 persons for each group, total 1,500 persons for about 3 weeks since September 1, 2016. The results of this study are as follows: (1) Based on the generation, there were significant differences in relevant categories of their visiting frequency, visiting purpose, visiting hour, transportation, companion, behavior during the wait and selection of a general hospital. (2) In all generation, they responded that they have visited once or twice per year. People in 20s and 30s responded that their visit for the hospital is to receive specific treatment, while other people in 40s, 50s and 60s visit the hospital majorly for routine check-ups. Therefore, it is imperative for a health check-up center to design an environmental plan that reflects the characteristics of elders in 40s, 50s and 60s. (3) People in 40s, 50s and 60s usually visit a general hospital in the mornings of weekdays, while generations in 20s and 30s responded that they mostly visit the hospital in the mornings of weekend. (4) When they visit a general hospital, people in their 20s are usually using public transportations, while people in their 30s to 60s are using their own vehicle. (5) People in their 20s majorly visited 'lobby'. In older generations, they tend to visit 'outpatient clinic'. Therefore, it is necessary to build an outpatient clinic environment that considers the elderly. (6) Patients majorly responded that they are using their cell phone, while waiting for their clinic call. In elder generations, they responded that they are more likely watching TVs, reading books/magazines or doing nothing. Therefore, it is essential to provide cell-phone related services and environmental supports. Visually attractive media can be utilized for this purpose.