• Title/Summary/Keyword: dominant effect

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Effect of Organic Farming on Spore Diversity of Arbuscular Mycorrhizal Fungi and Glomalin in Soil

  • Lee, Ji-Eun;Eom, Ahn-Heum
    • Mycobiology
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    • v.37 no.4
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    • pp.272-276
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    • 2009
  • In this study, eight soil samples were collected from organic and conventional farms in a central area of South Korea. Spore communities of arbuscular mycorrhizal fungi (AMF) and glomalin, a glycoprotein produced by AMF, were analyzed. Spores of Glomus clarum, G. etunicatum, G. mosseae, G. sp., Acaulospora longula, A. spinosa, Gigaspora margarita, and Paraglomus occultum were identified at the study sites, based on morphological and molecular characteristics. While Acaulospora longula was the most dominant species in soils at organic farms, Paraglomus occultum was the most dominant species in soils at conventional farms. Species diversity and species number in AMF communities found in soils from organic farms were significantly higher than in soils from conventional farms. Glomalin was also extracted from soil samples collected at organic and conventional farms and was analyzed using both Bradford and enzyme-linked immunosorbent assays. The glomalin content in soils from organic farms was significantly higher than in soils from conventional farms. These results indicate that agricultural practices significantly affect AMF abundance and community structure.

Effects of barrier height on electron scattering mechanisms in $\delta-doped$ InAlAs/InGaAs/InAlAs Heterostructures

  • Park, H.S.;Vang, S.J.;Kim, J.I.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07b
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    • pp.955-959
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    • 2004
  • The effects of conduction band offset on 2 dimensional electron gas (2DEG) in N-InAlAs(AlAsSb)/InGaAs/InAlAs (AlAsSb) metamorphic heterostructures (MMHS) are studied. A combination of the Shubnikov-deHaas oscillations and the Hall measurements is used to investigate the electron transport properties of these structures. The mobility in the second subband is higher than that in the first subband in all heterostructures. This is attributed to the fact that electrons in the first subband we, on average, closer to the interface and are therefore scattered more strongly by ionized impurities. The results suggest that intersubband scattering rate is more dominant in structures with higher conduction band offset whereas alloy scattering is found to be more dominant in the higher band offset system.

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Influence of Local Coercivity Variation on Magnetization Reversal Dynamics

  • Choe, Sug-Bong;Jang, Hyuk-Jae;Shin, Sung-Chul
    • Journal of Magnetics
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    • v.5 no.1
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    • pp.4-8
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    • 2000
  • Local coercivity variation of Co/Pd nanomultilayers has been investigated by measuring the polar Kerr hysteresis loops of local areas of submicron size using a magnetooptic Kerr microscope system. Interestingly, the local coercivity distribution is very sensitive to an increase in the number of repeats: the $(2-{\AA}\;Co/ll-{\AA} Pd)_10$ sample showed a smooth variation of the local coercivity, while $(2-{\AA}\;Co/ll-{\AA} Pd)_18$ showed a large fluctuation. From micromagnetic considerations based on a thermally activated relaxation odel, we have found that this local coercivity variation has a crucial effect on the contrasting magnetization reversal behavior observed in those samples: dominant wall-motion far the former sample and dominant nucleation for the latter one.

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NewHorizon: On the Quenching Mechanisms of the Dwarf Galaxies

  • Kim, Seonwoo;Rhee, Jinsu;Han, San;Choi, Hoseung;Yi, Sukyoung K.
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.1
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    • pp.53.1-53.1
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    • 2021
  • Dwarf galaxies are the most abundant objects in the universe. Hence, understanding the dwarfs is important but relatively little is known due to the lack of computing power and limitations in the telescope resolution. We thus use the state-of-the-art NewHorizon simulation, which is a set of cosmological hydrodynamical simulations, to dissect the quenching mechanism working on dwarf galaxies by inspecting the star formation and mass history of individual galaxies. It is known that internal (AGN, SN, stellar feedback) and external (major and minor mergers, ram pressure stripping, strangulation) mechanisms affect the quenching of dwarfs. Because of the combination of these mechanisms, periodicity in the star formation history of the dwarf galaxies is expected. To check for their periodicity, Fourier transform was performed on the star formation history. By comparing the physical timescales and the periodicity, we determine the dominant effect working on the dwarfs. Then, we compare the dominant effects working on the galaxies according to their varying properties.

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Effect of Environmental Variables on the Inter- and Subtidal Macrobenthic Communities in the Iwon Dike Area (이원방조제 주변의 조간대 및 조하대 대형저서동물의 군집과 환경요인과의 관계)

  • LEE Jae-Hac;YU Ok Hwan;LEE Hyung-Gon;PARK Ja-Yang
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.37 no.4
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    • pp.295-306
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    • 2004
  • Spatial patterns in the macrobenthic community structure in the inter- and subtidal zones in front of the Iwon Dike and environmental variables were examined in August 2001, In total, 156 macrobenthic species(123 intertidal species and 90 subtidal species) were recorded during this study, predominately polychaetes $(40{\%})$, bivalves $(22{\%})$, and crustaceans $(22{\%})$. Polychaetes made up less than $40{\%}$ of the intertidal communitr, but more than $50{\%}$ of the subtidal community. The mean density during this study was $1,456ind./m^{2}.$ Multivariate analysis (multidimensional scaling) revealed significant differences in community structure among four regions: near the Iwon dike (B1), the high and middle intertidal zone (B2), low intertidal zone (Al), and subtidal zone (A2). The number of species, total density, and diversity (H') varied significantly among the four regions. The distribution of macrobenthic community was affected by environmental variables, such as ${\%}$ silt/clay content, total sulfide, lose of ignition, and chemical oxygen demand. These environmental variables were negatively correlated with the dominant species (Nephtys polybranchia, Umbonium thomasi, and Scoloplos armiger) in the intertidal area, but positively correlated with the dominant species (Lumbrineris cruzensis, Notomastus latericeus, and Moerella sp.) in the subtidal area. Environmental variables $({\%}\;silt/clay content and total sulfide)$ were positively correlated with the dominant species (Heteromastus filiformis) in region Bl, but negatively correlated with the dominant species (Umbonium thomasi and Scoloplos koreanus) in region B2. Amphipods Urothoe spp. and Monoculodes koreanus were the dominant species in region Al. Umbonium thomasi, the dominant species in region B2, was not found in regions Bl or Al. We suggest that the inter-specific competition for territory and exposure to seawater may be important factors controlling the macrobenthic community structure in the inter- and subtidal zones in front of the Iwon Dike.

A Review on the Dominant Undertaking's Abuse in the Medical Device Market (시장지배적 의료기기 사업자의 경쟁제한적 차별행위 - 지멘스 사건을 중심으로 -)

  • Jeong, Jae Hun
    • The Korean Society of Law and Medicine
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    • v.23 no.1
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    • pp.81-119
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    • 2022
  • Medical device market is strongly related with health care market. Public regulation in medical device market tends to be more lenient than health care market. In this market, competition law, administrative law and intellectual property law are intertwined, and thereby a variety of legal issues could be developed. Recently, dominant undertaking's abuse case was dealt with KFTC(Korea Fair Trade Commission) and Seoul High Court. The issues were whether dominant undertaking discriminated trading partners and this discrimination was anticompetitive. In this case, Seoul High Court revoked the KFTC's decision, holding that the undertaking did not harm competition, though it has dominant power in the relevant medical device market. This decision would be a meaningful precedent, not only that there have been small numbers of dominance abuse cases in Korea, but also that this case happened in medical device market. This case dealt with various issues like market definition, market power, alleged abuse and its anticompetitive effect. The court held that medical device markets are distinguished from medical device repairing market. However, the court did not clarify that medical device repairing market is a single branded market only for repairing the plaintiff's medical devices. Second, plaintiff's dominance is based on the lock-in effect, which means that hospitals could not switch devices like CT or MRI from plaintiff to other competitors. This could be supplemented from the fact that medical devices are expensive and the using period are significantly long. However market definition based on single branded market theory could be applied in rare and exceptional cases. Therefore the general application of single branded market theory might result in overestimate of market power. This type of abuse pattern requires improper condition contrary to resonable trade practice. KFTC asserted free charge for plaintiff's copy right. However, it is not clear whether the cases for free charge are general or not. Even if so, the intention and motive of providers for free charge should be proved. The main issue of anticompetitive effect was whether plaintiff raised rival's cost. Competitor's cost was increased due to plaintiff's copy right and its license fee. However the charge for license could be within the scope of fair and legal exercise of copy right. If competitors are excluded due to legal exercise of copy right or efficiency, the exclusionary abuse could not be proved.

The Effect of Necktie Color and Patterns on the Image Formation of the Men's Suit (넥타이의 색과 무늬가 남성복 이미지에 미치는 영향)

  • 강경자;임지영
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.5
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    • pp.753-768
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    • 1996
  • The purpose of this study is to find out the effect of suit color, necktie color and necktie patterns on the men's suit image formation. The experimental materials developed for this study were a set of stimuli and response scales. The stimuli were 28 color pictures manipulated with suit color, necktie color and necktie patterns by computer drawing. The experimental design consists of 3 factorial design; 1) suit color (navy blue, beige), 2) necktie color (analogous, complimentary color), 3) necktie patterns (plain, dot, stripe, check, paisley, floral, abstract) The 7-point semantic differential response scale designed for visual evaluation of men's suit image on suit color, necktie color and necktie patterns were composed of 34 bipolar adjectives. The subject are 150 female undergraduate students in Chin-ju city. They responded twice to 14 stimuli at random order The result of this study are as follows; 1. By analyzing the responses of the subjects, 4 factors emerged in the dimensional structure of the men's suit image formed by suit color, necktie color and necktie patterns. The 4 factors are charm, potency, uniqueness and tenderness. Among these, charming and potential factors proved to be more important. 2. necktie color, suit color and neckite patterns had the significant effect on the formation of men's suit image. In the charm image, only necktie patterns were proved to be the most dominant variable. The most dominant variable in the potencial and unique image was necktie color and second to it suit color was important. But suit color was most significant in the image of tenderness. 3. In the effects of interactions between each variables, the combination of suit color and necktie color wins more significant than that of suit color and necktie patterns and that of necktie color and necktie patterns, but in the image of tenderness, only the combination of suit color and necktie color was more significant. In the interaction of suit color, necktie color and necktie patterns, the potential factor didn't have the significant effect.

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Analysis of Gene for Major Quantitative Characters in Silkworm, Bombyx mori (가잠의 주요 양적 형질에 관한 유전분석)

  • 손봉희;정원복
    • Journal of Sericultural and Entomological Science
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    • v.34 no.1
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    • pp.21-29
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    • 1992
  • In the experiment, gene actions were analyzed for seven silkworm varieties in order to obtain basic information on their genetic improvement by diallel crosses. The results obtained were summarized as follows : in analysis of variance, significantly maternal and reciprocal effects were observed for all character except female cocoon shell percentage and female pupal weight. Over-dominance was shown by Vr-Wr graphic analysis in three characters such as female cocoon weight, female and male pupal weight, and partial dominance in five characters such as male cocoon weight, cocoon shell percentage in both female and male. Component of genetic varience analyzed for five characters such as male cocoon weight, cocoon shell weight, cocoon shell percentage in both female and male showed that additive effects were higher than dominant effects, and female cocoon weight showed dominant effects higher than additive effects. Heritability of narrow sence was higher more than 0.51 and heritability of broad sence was higher more than 0.77 in all characters except for female pupal weight. The directions of dominance were negative for female cocoon shell weight and somewhat higher for female and male cocoon shell percentage. Meanwhile cocoon weight, pupal weight in both female and male showed positive in the direction of dominance.

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Genetic Analysis of Six Panicle Characters in Rice (수도의 수당구성요소의 유전분석)

  • 김주현
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.32 no.2
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    • pp.208-214
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    • 1987
  • A genetic study on the panicle characters in Oryza sativa was carried out by means of a 5 x 5 diallel cross. The five parental varieties were Raekyung, Yeongnamjosaeng, Nongbaek, Yushin and Honenwase. All characters were correlated positively each other, except number of kernels per primary branch. The number of secondary branches per primary branch.was the most effective factor in determining the number of kernels per panicle, the next being the number of primary branches per panicle. Regression analyses of the data of Vr/Wr indicated the presence of non-allelic gene interactions for all characters. Overdominant characters were the number of kernels per panicle, the number of primary branches per panicle, the number of secondary branches per primary branch, the number of kernels per primary branch and sum of kernels on all the tertiary branches per panicle, suggesting that the characters were more influenced by dominant effect than additive effect. However, the number of kernels per secondary branch was partially dominant where the genetic variation was due more to additive effect than to dominance effect. But after omitting the parent which had non-allelic interaction gene, the characters; the number of kernels per panicle, the number of secondary branches per primary branch, and the number of kernels per secondary branch, were partially dominant. Narrow sense heritabilities(h$^2$ N) in number of kernels per panicle and number of secondary branches were high and moderate, respectively, but those of the rest were lower. Mean squares of GCA and SCA of all characters, except SCA of the number of kernels per secondary branch, were highly significant. Effects of GCA were larger than SCA effects in all characters. Raekyung, Yushin and Nongbaek had highly positive GCA, and the best positive SCA was observed in crosses of Nongbaek x Tongillines (Raekyung, Yushin, and Yeongnamjosaeng) in all characters.

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Induction of apoptosis by etoposide treatment in colon cancer cell line SNU C2A (대장암 세포주 SNU C2A에서 etoposide 처리에 의한 apoptosis 유도)

  • Jung, Ji-Yeon;Na, Yun-sook;Jung, Ho-Chul;Oh, Sang-Jin
    • IMMUNE NETWORK
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    • v.1 no.3
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    • pp.221-229
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    • 2001
  • Background: Inactivation of tumor suppressor genes is believed to be important in the development of many human malignancies. Recently, several lines of evidence have indicated that the wild type p53 gene located at 17p13.3, may function as a tumor suppressor gene and that a mutant p53 gene could promote transformation by inactivating normal p53 function in a dominant negative fashion. These broad spectrum of p53 mutation in human cancers provide that mutant p53 and their protein may be potential targets of tumor diagnostic and therapeutic interventions. Method: Colony formation was performed to investigate growth suppressional ability. p53 expression pattern was examined by western blot and p53-mediated transactivation ability was assessed by CAT activity. SNU C2A cells were observed in apoptotic aspects induced by etoposide and $H_2O_2$ treatment, detecting sensitivity on agent, DNA fragmentation through agarose gel, chromatin condensation by fluorescence microscope, and cell cycle distribution by FACS. Result: 1) p53 mutant his179arg ($histidine{\rightarrow}arginine$) detected in SNU C2A cells lost transcriptional activity and growth suppression ability, showing dominant negative effect on its wild type p53. 2) Etoposide-treated SNU C2A cells induced apoptosis, exhibiting dramatic reduction of cell growth, DNA fragmentation, nuclear condensation formation of apoptotic body and increment of sub-G1 cell fraction. 3) Etoposide and $H_2O_2$-treated SNU C2A cells have no high increase of p53 expression and overexpressed p53 protein changed localization, from cytoplasm to nucleus. Also, p53-mediated transcriptional activity was increased by agents-treatment. Conclusion: SNU C2A cells coexpress wild-type and mutant p53 protein induced apoptosis in the condition on DNA damage, through localizational shift from cytoplasm to nucleus of p53 protein rather than the induction of p53 protein. SNU C2A cells derived mutant p53 his179arg abrogated both the growth supression ability and transactivational activity, showing inhibition effect on transcriptional activity of wild type p53, but did not repress the activity of wild type p53 in SNU C2A cells owing to dominant activity of wild type. These cell condition may provide new gene therapeutic implications leading effective antiproliferation of cell when mutant and wild-type p53 protein were co-expressed in cell.

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