• Title/Summary/Keyword: NOR

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Identification of Nucleolus Organizer Regions of Korean Cattle Chromosomes by AgNOR Staining (AgNOR 염색법에 의한 한우 염색체의 Nucleolus Organizer Regions 양상 분석)

  • Jung , W.;Sohn, S.H.
    • Journal of Animal Science and Technology
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    • v.45 no.5
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    • pp.695-702
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    • 2003
  • Nucleolus Organizer Regions (NORs) are the specific chromosome sites where ribosomal genes are located and highly expressed. We have applied the AgNOR staining to identify the distribution of NORs in the chromosomes of Korean Cattle. We have also studied the NORs pattern on the cells originated from different breeds, tissues and sex. Peripheral blood from forty-four Korean Cattle and Holstein was cultured for chromosme preparation. The fibroblast culture from biopsied ear skins was also conducted for chromosome analysis. The distribution of NORs was analyzed by sequential Ag staining and G-banding on metaphases of the cells. In Korean Cattle, the NORs are localized on the telomeres of the five chromosome pairs number 2, 3, 4, 11 and 28. The number of NORs per metaphase ranged from 2 to 10 giving a mean value of 5.6. The number of NORs per cell varied among individuals and cells within same individual. The size of NORs also differed in NO-chromosomes. The number of NORs was significantly different between Korean Cattle and Holstein, fibroblasts and lymphocytes, and male and female. However, the distribution and frequency of NORs were similar among the cells regardless of breeds, tissues, and sex.

Antifungal Activity of Nor-securinine Against Some Phytopathogenic Fungi

  • Sahni, Sangita;Maurya, S.;Singh, U.P.;Singh, A.K.;Singh, V.P.;Pandey, V.B.
    • Mycobiology
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    • v.33 no.2
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    • pp.97-103
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    • 2005
  • Crude extracts and active principles from medicinal plants have shown potential role in controlling plant diseases in glasshouses as well as in fields as one of the safest and ecofriendly methods. The effect of nor-securinine (an alkaloid) isolated from Phyllanthus amarus has been seen against spore germination of some fungi (Alternaria brassicae, A. solani, Curvularia pennisetti, Curvularia sp., Erysiphe pisi, Helminthosporium frumentacei) as well as pea powdery mildew (Erysiphe pisi) under glasshouse conditions. The sensitivity of fungi to nor-securinine varied considerably. Nor-securinine was effective against most of the fungi. H. frumentacei was more sensitive even at the lowest concentration ($1,000\;{\mu}g/ml$). Likewise conidia of E. pisi were also inhibited in partially or completely appressorium formation. Pre-inoculation treatment showed greater efficacy than post-inoculation in inhibiting powdery mildew development on pea plants in a glasshouse. Maximum inhibition occurred at $2000\;{\mu}g/ml$.

Importance of C-26 Demethylation for Homeostatic Regulation of Brassinosteroids in Seedling Shoots of Zea mays L (옥수수 유식물 신초에서 Brassinosteroids의 항상성 조절을 위반 C-26 탈메틸 반응의 중요성)

  • Park, Hyun-Hee;Kim, Young-Soo;Kim, Seong-Ki
    • Journal of Plant Biotechnology
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    • v.33 no.1
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    • pp.65-73
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    • 2006
  • Regulatory mechanism for endogenous levels of castasterone (CS) and its biosynthetic precursors in shoots of maize was investigated by the use of enzyme solution prepared from the plant tissue. When [$^2H_0$]- and [$^2H_6$]-CS was used as substrates, [$^2H_0$]-26-norCS and [$^2H_3$]-28-norCS were identified as products, indicating that [$^2H_0$]- and [$^2H_6$]-CS are differently metabolized into [$^2H_0$]-26-norCS and [$^2H_3$]-28-norCS by C-26 and C-28 demethylation, respectively. This suggests that both C-26 and C-28 demethylation can be involved in CS catabolism. In fact that C-28 demethylation only occurred when isotope labeled substrate was used, however, C-26 demethylation is thought be a natural reaction occurred in the maize shoots. When 6-deoxoteasterone (6-deoxoTE) was used, 6-deoxo-26-norTE and 3-dehydro-6-deoxo-26-norTE as well as 6-deoxo-3-dehydroTE and 6-deoxotyphasterol (6-deoxoTY) were identified as enzyme products. When 6-deoxoTY was added, 6-deoxo-26-norTY as well as 6-deoxo-3-dehydroTE and 6-deoxoTE was identified as products. These indicate that C-26 demethylation of 6-deoxoTE, 6-deoxo-3-dehydroTE and 6-deoxoTY as well as a reversible C-3 epimerization from 6-deoxoTE to 6-deoxoTY intermediated by 6-deoxo-3-dehydroTE are operative in the maize shoots, demonstrating that endogenous levels of biosynthetic precursors of CS are also controlled by C-26 demethylation. Therefore, it is thought that C-26 demethylation is an important and a common deactivation process which functions to maintain steady state levels of endogenous brassinosteroids in the maize shoots.

Optical Implementation of Bipolar Hopfield Neural Network Model by using EX-NOR Logic Operation (EX-NOR 논리 연산을 이용한 Bipolar Hopfield 신경 회로망 모델의 광학적 실현)

  • 박성철;김은수;양인응;박한규
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.10
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    • pp.1591-1597
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    • 1989
  • Through the matematical alaysis of EX-NOR logic relation between the input vector and the memory matrix, we propose a new method for optical implementation of the bipolar Hopfield neural network model based on the optical vector-matrix multiplier.

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The Chiroptical Properties and Absolute Configuration of 28-nor-$\beta$-amyrins

  • Woo, Won-Sick
    • Archives of Pharmacal Research
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    • v.14 no.2
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    • pp.160-164
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    • 1991
  • The existence in nature of two isomers of 28-nortriterpenes is known. One is normal D/E cis form and the other is $17\alpha$-hydrogen D/E trans form. Since the latter cannot exist with ring D in the chair conformation, the chiroptical method is not applicable to determination of the absolute configuration. The stereochemical assignment would now be made by NMR data. Confirmation of this view could be provided by the synthesis of $3\beta, 21\beta-{dihydroxy-16-keto-28-nor-17}\alpha, \;18\beta-{olean-12-ene}$ as a model compound.

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Improvement of micronucleus assay in the lymphocytes using Argyrophilic nucleolor organizer region(AgNOR) staining (Argyrophilic nucleolar organizer region(AgNOR) 염색을 이용한 림프구의 미세핵분석법의 개선)

  • Kim, Sung-ho;Han, Dong-un;Kang, Mun-il;Lim, Jeong-taek
    • Korean Journal of Veterinary Research
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    • v.36 no.2
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    • pp.277-281
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    • 1996
  • A technique to improve the analysis of micronuclei(MN) in lymphocytes as a cytogenetic indicator is reported. For the purpose of diminishing the variation of the result from individual reader and making it easier to distinguish accurately a cytokinesis blicked(CB) lymphocyte and micronuclei, we tried a modified one-step silver staining technique as a method for detection of the argyrophilic nucleolar organizer region(AgNOR) with or without conventional Giemsa stain in the slide from CB method. Compared with the conventional Giemsa stain, the preparation processed with this method are especially useful for the accurate analysis of MN of cultured lymphocyte with cytochalasin B. This method will be a useful technique for automated calculation of MN.

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Analysis of flash memory characteristics as storage medium of mobile equipments (휴대단말기 저장매체인 플래시 메모리 특성 분석)

  • Jung, Bo-Sung;Lee, Jung-Hoon
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.10 no.4
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    • pp.115-120
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    • 2011
  • Recently flash memory is widely used in various mobile devices as storage medium. Nonvolatile memory can be divided into two categories: NAND- and NOR-type flash memory. NOR flash memory is mainly used to store instruction codes for operation; while NAND for data storage. However, NAND does show more economical benefits, that is, it is approximately 30~40% cheaper than NOR flash. Therefore it can be useful to improve NAND flash performance by replacing NOR flash with NAND flash combining with various buffer systems.

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Urinary Metabolism and Excretion of Carbinoxamine after Oral Administration to Man

  • Jung, Byung-Hwa;Chung, Bong-Chul;Park, Jong-Sei
    • Biomolecules & Therapeutics
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    • v.4 no.3
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    • pp.251-256
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    • 1996
  • The metabolism of carbinoxamine, 2-[(4-chlorophenyl)-2-pyridinyl-methoxy]-N, N-dimethylethaneamine, was studied in adult male volunteers after an oral dose of 15 mg. Solvent extracts of urine obtained with or without enzyme hydrolysis were analyzed by gas chromatography-mass spectrometry after derivatization with MSTFA/TMSCl (N-methyl-N-trimethylsilyltrifluoroacetamide/trimethyl chlorosilane). The structures of metabolites were determined based on the electron impact (EI) and chemical ionization (CI) mass spectra. Nonconjugated metabolites identified in the urine were carbinoxamine, nor-carbinoxamine, and bits-nor-carbinoxamine. Parent drug, nor-carbinoxamine, and bits-nor-carbinoxamine were also detected as conjugated forms. These metabolites observed in human urine were different from those previously reported in the rat. Urinary excretions of carbinoxamine were reached to maxima in 4 hours after drug administration with 4.9%-8.1% and 2.5-4.2% of the dose excreted during 24 h as carbinoxamine and its glucuronide, respectively.

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A Study for Design and Application of Self-Testing Comparator (자체시험 (Self-Testing) 특성 비교기(Comparator)설계와 응용에 관한 연구)

  • 정용운;김현기;양성현;이기서
    • Proceedings of the KSR Conference
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    • 1998.05a
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    • pp.408-418
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    • 1998
  • This paper presents the implementation of comparator which is self-testing with respect to the faults caused by any single physical defect likely to occur in NMOS and CMOS integrated circuit. The goal is to use it for the fault-tolerant system. First, a new fault model for PLA(Programmable Logic Array) is presented. This model reflects several physical defects in VLSI circuits. It focuses on the designs based on PLA because VLSI chips are far too complex to allow detailed analysis of all the possible physical defects that can occur and of the effects on the operation of the circuit. Second, this paper shows that these design, which has been implemented with 2 level AND-ORor NOR-NOR circuit, are optimal in term of size. And it also presents a formal proof that a comparator implemented using NOR-NOR PLA, based on these design, is sol f-testing with respect to most single faults in the presented fault model. Finally, it discusses the application of the self-testing comparator as a building block for the implementation of the fault-tolerant system.

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Realization of Two-bit Operation by Bulk-biased Programming Technique in SONOS NOR Array with Common Source Lines

  • An, Ho-Myoung;Seo, Kwang-Yell;Kim, Joo-Yeon;Kim, Byung-Cheul
    • Transactions on Electrical and Electronic Materials
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    • v.7 no.4
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    • pp.180-183
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    • 2006
  • We report for the first time two-bit operational characteristics of a high-density NOR-type polysilicon-oxide-nitride-oxide-silicon (SONOS) array with common source line (CSL). An undesired disturbance, especially drain disturbance, in the NOR array with CSL comes from the two-bit-per-cell operation. To solve this problem, we propose an efficient bulk-biased programming technique. In this technique, a bulk bias is additionally applied to the substrate of memory cell for decreasing the electric field between nitride layer and drain region. The proposed programming technique shows free of drain disturbance characteristics. As a result, we have accomplished reliable two-bit SONOS array by employing the proposed programming technique.