• Title/Summary/Keyword: Pr

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The Effect of Pr Additive on Magnetostriction of Amorphous Fe-B Alloy (Pr 첨가가 Fe-B 비정질합금의 자왜에 미치는 영향)

  • 조용수;김윤배;김창석;김택기
    • Journal of the Korean Magnetics Society
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    • v.4 no.2
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    • pp.126-129
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    • 1994
  • In order to invetigate the effect of Pr additive on the magnetostriction of amorphous Fe-B alloys, amorphous $Fe_{86-x}B_{14}Pr_{x}(2{\leq}x{\leq}8\;at.%)$ alloys were prepared by a rapid solidification process. As the Pr content increased in the as-prepared amorphous $Fe_{84}B_{14}Pr_{2}$ alloy annealed at $300^{\circ}C$ for 2 hr increased to 70 ppm. Ac power loss and permeability$(f=50\;kHz,\;B_{m}=0.1\;T)$ of the annealed amorphous $Fe_{84}B_{14}Pr_{2}$ alloy were 15 W/kg and $5.5{\times}10^{3}$, respectively.

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Pueraria lobata Ohwi as an Osteoporosis Therapeutics (칡의 부위별 골다공증 치료효과)

  • Kim, Chung-Sook;Ha, Hye-Kyung;Kim, Hye-Jin;Lee, Je-Hyun;Song, Kye-Yong
    • Korean Journal of Food Science and Technology
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    • v.34 no.4
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    • pp.710-718
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    • 2002
  • It is reported that Pueraria Radix contains phtoestrogens whereas flower, and bud of Pueraria lobata Ohwi were not known. In the present study, we determined the amount of phytoestrogen in each portion of P. lobata Ohwi and carried out therapeutic effects of osteoporosis. The amounts of genistein, daidzein, and formononetin in Pueraria Radix (PR), Pueraria Flos (PF), and young Pueratia Folium (PL) were quantitated using a HPLC system. Proliferation of osteoblast and growth inhibitory effect on osteoclast were measured in order to screen their effects on osteoporosis. Proliferation of osteoblast-like cells (Saos-2) was analyzed by both MTT methods and alkaline phosphatase (ALP) assays. Growth inhibitory effect on osteoclast was also detected as Tartrate resistant acid phosphatase (TRAP) assay. Ovariectomized rat as an in vivo animal model was selected and administrations of PR were 1 g/kg/day (PR-1) and 5 g/kg/day (PR-5) for 9 weeks, respectively. Trabecular bone areas (TBAs) of tibia and lumbar were analyzed usibg histomorphological methods. Results show that PR contains the highest level of daidzein ($10435{\pm}2143\;mg/kg$ of dried herb) and stimulated ALP activity, approximately 160% of the control. Growth inhibitory effect on osteoclast by both PR and daidzein were almost identical with control although $IC_{50}$ of genistein was $5.81{\times}10^{-7}$ M. Increases in body weight of OVX rats were suppressed by administration of PR but wet weights of uterus in PR-5 group were increased (p<0.05). Plasma ALP and HDL-cholesterol levels were decreased following ages (p<0.01), and LDL-cholesterol level was also decreased in PR-5 group at 20 week of age (p<0.01). TBAs of tibia and lumbar in PR-1 and PR-5 groups were higher than those of the control although the values were less than those of the sham group (each p<0.01) In conclusion, administrations of PR prevented loss of TBAs of tibia and lumber in OVX rats, while PL and PF did not (p<0.01).

Biochemical Analysis of Interaction between Kringle Domains of Plasminogen and Prion Proteins with Q167R Mutation

  • Lee, Jeongmin;Lee, Byoung Woo;Kang, Hae-Eun;Choe, Kevine K.;Kwon, Moosik;Ryou, Chongsuk
    • Journal of Microbiology and Biotechnology
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    • v.27 no.5
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    • pp.1023-1031
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    • 2017
  • The conformational change of cellular prion protein ($PrP^C$) to its misfolded counterpart, termed $PrP^{Sc}$, is mediated by a hypothesized cellular cofactor. This cofactor is believed to interact directly with certain amino acid residues of $PrP^C$. When these are mutated into cationic amino acid residues, $PrP^{Sc}$ formation and prion replication halt in a dominant negative (DN) manner, presumably due to strong binding of the cofactor to mutated $PrP^C$, designated as DN PrP mutants. Previous studies demonstrated that plasminogen and its kringle domains bind to PrP and accelerate $PrP^{Sc}$ generation. In this study, in vitro binding analysis of kringle domains of plasminogen to Q167R DN mutant PrP (PrPQ167R) was performed in parallel with the wild type (WT) and Q218K DN mutant PrP (PrPQ218K). The binding affinity of PrPQ167R was higher than that of WT PrP, but lower than that of PrPQ218K. Scatchard analysis further indicated that, like PrPQ218K and WT PrP, PrPQ167R interaction with plasminogen occurred at multiple sites, suggesting cooperativity in this interaction. Competitive binding analysis using $\small{L}$-lysine or $\small{L}$-arginine confirmed the increase of the specificity and binding affinity of the interaction as PrP acquired DN mutations. Circular dichroism spectroscopy demonstrated that the recombinant PrPs used in this study retained the ${\alpha}$-helix-rich structure. The ${\alpha}$-helix unfolding study revealed similar conformational stability for WT and DN-mutated PrPs. This study provides an additional piece of biochemical evidence concerning the interaction of plasminogen with DN mutant PrPs.

Leaf-specific pathogenesis-related 10 homolog, PgPR-10.3, shows in silico binding affinity with several biologically important molecules

  • Han, Jin Haeng;Lee, Jin Hee;Lee, Ok Ran
    • Journal of Ginseng Research
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    • v.39 no.4
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    • pp.406-413
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    • 2015
  • Background: Pathogenesis-related 10 (PR-10) proteins are small, cytosolic proteins with a similar three-dimensional structure. Crystal structures for several PR-10 homologs have similar overall folding patterns, with an unusually large internal cavity that is a binding site for biologically important molecules. Although structural information on PR-10 proteins is substantial, understanding of their biological function remains limited. Here, we showed that one of the PgPR-10 homologs, PgPR-10.3, shares binding properties with flavonoids, kinetin, emodin, deoxycholic acid, and ginsenoside Re (1 of the steroid glycosides). Methods: Gene expression patterns of PgPR-10.3 were analyzed by quantitative real-time PCR. The three-dimensional structure of PgPR-10 proteins was visualized by homology modeling, and docking to retrieve biologically active molecules was performed using AutoDock4 program. Results: Transcript levels of PgPR-10.3 expressed in leaves, stems, and roots of 3-wk-old ginseng plantlets were on average 86-fold lower than those of PgPR-10.2. In mature 2-yr-old ginseng plants, the mRNA of PgPR-10.3 is restricted to leaves. Ginsenoside Re production is especially prominent in leaves of Panax ginseng Meyer, and the binding property of PgPR-10.3 with ginsenoside Re suggests that this protein has an important role in the control of secondary metabolism. Conclusion: Although ginseng PR-10.3 gene is expressed in all organs of 3-wk-old plantlets, its expression is restricted to leaves in mature 2-yr-old ginseng plants. The putative binding property of PgPR-10.3 with Re is intriguing. Further verification of binding affinity with other biologically important molecules in the large hydrophobic cavity of PgPR-10.3 may provide an insight into the biological features of PR-10 proteins.

What explains the failure of Google in the Korean market? The Impact of Multicultural PR Strategy

  • Kim, Hyejung;Woo, Wonseok;Kang, Hyoung-goo
    • Asia Marketing Journal
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    • v.14 no.4
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    • pp.35-56
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    • 2013
  • The era of globalization provides us with both opportunities and threats. The success of a multinational corporation depends largely on its ability to adapt itself to new market environment. We believe that understanding and implementing multicultural PR strategy can be a key to the multinational corporations' success in foreign markets. We argue in this paper that even a global iconic company such as Google needs to focus on how to understand local consumers' needs and preferences before formulating and implementing PR strategy. Having a global hit product or service is not sufficient enough to be successful in some foreign markets. It is especially more evident in the industries where companies deal with individual consumers, and perceptions and sentiments play a large role in their purchase decisions. The objective of this research is to find out the relationship between multicultural PR strategy and business performance. Therefore, our main hypothesis is; better implementation of multicultural PR strategy by a multinational corporation will result in higher performance in the foreign markets. To prove the relationship between multicultural PR strategy and performance, we designed a framework that uses Rudan's (2004) five rules for multicultural PR strategy. It is a contribution to the business academics as there are very few studies that directly focus on and analyze the multicultural aspects of a multinational company's PR strategy. Through our research, we found strong evidence that there is a positive relationship between the level and effectiveness of a company's multicultural PR strategy and its performance in the foreign markets. This offers some meaningful implications to the managers of the multinational corporations and those who are considering going into a foreign market for the first time. We also suggested a way of measuring the implementation of multicultural PR strategy. By applying five rules for multicultural PR strategy to Google's PR activities, it allowed us to convert qualitative information into quantitative data. This kind of tool can be helpful for multinational corporations that want to evaluate their own PR activities.

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Effects of Sodding and Seeding Time and Rate of Seed Mixture on the Establishment of Cool-Season Turfgrasses (한지형 잔디의 조성시기, 초종 혼합 비율이 잔디 피복에 미치는 영향)

  • Shim Gyu Yul;Kim Chang Soo;Lee Seong Ho;Joo Young Kyoo
    • Asian Journal of Turfgrass Science
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    • v.18 no.4
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    • pp.179-191
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    • 2004
  • This study was conducted to find out the effect of sodding and seeding time and rate of seed mixtures on the establishment of cool-season turfgrasses by evaluating the turf coverage rates for two years. In fall planting, the required establishment period of full coverage($100\%$) was 1.5 months with a rolled turf sodding(Kentucky bluegrass $100\%$, Kentucky bluegrass $80\%$+perennial ryegrass $20\%$). The $100\%$ turf establishment was achieved in 7 months with Perennial ryegrass $100\%$, and 7.5 months by seeding with Kentucky bluegrass $100\%$(KB 100), Kentucky bluegrass $80\%$+perennial ryegrass $20\%$(KB80+PR20), Kentucky bluegrass $70\%$+perennial ryegrass $30\%$(KB70+PR30). In spring planting, the establishment periods far sod with KB 100 or KB80+PR20 were taken one month. However, in the case of seeding, the establishment periods were 3 months, 3.5 months, 3.5 months and 4 months with PR100, KB80+PR20, KB70+PR30, and KB 100, respectively Comparing the turf establishment vigor between fall and spring planting, the vigor was higher In spring planting than in fall planting in both sodding and . seeding. In the case of spring planting, the most proper time for turf establishment was tested on April, May, and June trials. The effect was significant in establishment vigor. The result showed highest on April planting. On May and June trials, establishment vigors were decreased gradually As the mixture rate of PR increased, ryegrass, establishment vigor was decreased with the rates. These results indicated that perennial ryegrass has relatively less tolerant to summer heat than Kentucky bluegrass. Number of shoots in 95 days after seeding was higher in KB100 by 16,600 per $m^2$ than in PR100 by 12,400 per $m^2$, while the lowest number showed in KB50+PR50 by 3,300 per $m^2$. Those in KB80:PR20, KB70:PR30 were 6,700 and 4,900 per $m^2$, respectively. The ratios of tillers according to mixture rates between Kentucky bluegrass and perennial ryegrass were KB80:PR20=87:13, KB70:PR30=78:22, and KB50:PR50=48:52. According to results in this study, Ideal seeding time might be spring (April) than in fall (September), and proper mixture rate was $80\%$ of Kentucky bluegrass with $20\%$ of perennial ryegrass.

Knowledge Representation and Fuzzy Reasoning in the Level of Predicate Logic based on Fuzzy Pr/T Nets (퍼지 Pr/T 네트를 기반으로 하는 술어논리 수준의 지식표현과 퍼지추론)

  • 조상엽;이동은
    • Journal of Internet Computing and Services
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    • v.2 no.2
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    • pp.117-126
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    • 2001
  • This paper presents fuzzy Pr/T nets to represent the fuzzy production rules of a knowledge-based system in the level of first-order predicate logic. The fuzzy Pr/T nets are fuzzy extension of the Pr/T nets. Based on the fuzzy Pr/T net, we propose a fuzzy reasoning algorithm. This algorithm is much closer to human intuition and reasoning than other methods because of using the proper belief functions according to fuzzy concepts in fuzzy production rules.

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Synthesis and Reactions of Organoruthenium(Ⅲ) Complexes (새로운 3가 유기루테늄 착물의 합성과 반응)

  • Lee Dong-Hwan;Kim Hag-Gu;Seo Dae-Ryong;Kim Byung-Soon
    • Journal of the Korean Chemical Society
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    • v.37 no.1
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    • pp.98-104
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    • 1993
  • The paramagnetic organoruthenium(III) complexes $({\eta}^5-C_5Me_5)RuCl_2(PR_3) (PR_3 = PMe_3,\;PEt_3,\;PiPr_3,\;PCy_3,\;PMe_2Ph,\;PMePh_2,\;PPh_3,\;P(p-C_6H_4CH_3)_3$, DPPE, DPPB, Py) (2a∼2k) were synthesized by the reaction of $[({\eta}^5-C_5Me_5)RuCl_2]_2$ (1) with 1 equivalent of the corresponding phosphines $(PR_3)$. The effective magnetic moment ((${\mu}_{eff} = 1.65∼2.07 B.M.$)) derived from the magnetic susceptibility measurements of the complexes (2a∼2k) were consistent with the presence of a "single" unpaired electron in the molecule. Treatment of dichlororuthenium (III) complex ({\eta}^5-C_5Me_5)RuCl_2(PR_3)$ (2) (i) with KBr in acetone afforded the dibromoruthenium (III) complex $({\eta}^5-C_5Me_5)RuBr_2(PR_3) (PR_3 = PPh_3)$, (ii) with sodium amalgam in diethylether led to the bis(phosphine) derivatives $({eta}^5-C_5Me_5)RuCl(PR_3)_2 (PR_3 = PMe_3,\;PMePh_2)$, and (iii) with carbonmonoxide gave to the carbonyl derivatives $({\eta}^5-C_5Me_5)RuCl(PR_3)(CO) (PR_3 = PMe_3,\;PPh_3)$.

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The Estrogen Receptor Negative-Progesterone Receptor Positive Breast Carcinoma is a Biological Entity and not a Technical Artifact

  • Ng, Char Hong;Pathy, Nirmala Bhoo;Taib, Nur Aishah;Mun, Kein Seong;Rhodes, Anthony;Yip, Cheng Har
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1111-1113
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    • 2012
  • The ER-/PR+ breast tumor may be the result of a false ER negative result. The aim of this study was to investigate whether there is a difference in patient and tumor characteristics of the ER-/PR+ phenotype in an Asian setting. A total of 2629 breast cancer patients were categorized on the basis of their age, ethnicity, tumor hormonal receptor phenotype, grade and histological type. There were 1230 (46.8%) ER+/PR+, 306 (11.6%) ER+/PR-, 122 (4.6%) ER-/PR+ and 972 (37%) ER-/PR-. ER-/PR+ tumors were 2.5 times more likely to be younger than 50 years at diagnosis (OR: 2.52; 95% CI: 1.72-3.67). Compared to ER+/PR+ tumors, the ER-/PR+ phenotype was twice more likely to be associated with grade 3 tumors (OR:2.02; 95%CI: 1.00-4.10). In contrast, compared to ER-/PR- tumors, the ER-/PR+ phenotype was 90% less likely to be associated with a grade 3 tumor (OR: 0.12; 95%CI:0.05-0.26), and more likely to have invasive lobular than invasive ductal histology (OR: 3.66; 95%CI: 1.47-9.11). These results show that the ER-/PR+ phenotype occurs in a younger age group and is associated with intermediate histopathological characteristics compared to ER+/PR+ and ER-/PR- tumors. This may imply that it is a distinct entity and not a technical artifact.

Studies on Improving the Physical Properties of Pr-Fe-B System Rare-Earth Magnets (Pr-Fe-B계 희토류 자석의 물리적 특성 향상에 관한 연구)

  • 고재귀;임상희
    • Journal of the Korean Magnetics Society
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    • v.6 no.5
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    • pp.305-309
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    • 1996
  • To obtain the Pr-Fe-B ternary system magnets with higher $(BH)_{max}$, the effect of composition ratio and various heat-treatment temperatures on the magnetic properties of Pr-Fe-B system rare-earth magnets were investigated. The magnets with various composition of Pr and Fe were heat-treated at $990^{\circ}C$, $625^{\circ}C$, $585^{\circ}C$, $550^{\circ}C$ after sintering. Curie temperature is $310^{\circ}C$ and quantitative analysis by SEM, EDX shows that the $Pr_{2}Fe_{14}B$, Pr-rich phase consist of Pr~14 at.% and Fe~86 at.%, Pr~58 at.% and Fe~42 at.%, respectively. The coercivity is decreased after heat-treating at $990^{\circ}C$ and increased from 5.6 to 6.3 kOe at $625^{\circ}C$. The maximum energy product is decreased from 43.4 to 30.3 MGOe after the heat-treating at $990^{\circ}C$ but increased from 42.7 to 45.0 MGOe, about 5 %, by heat-treating at $625^{\circ}C$.

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