• Title/Summary/Keyword: Pi-b

Search Result 829, Processing Time 0.027 seconds

Antimutagenic Potential of Phellinus igniarius

  • Shon, Yun-Hee;Lee, Jae-Sung;Lee, Hang-Woo;Nam, Kyung-Soo
    • Journal of Microbiology and Biotechnology
    • /
    • v.9 no.4
    • /
    • pp.525-528
    • /
    • 1999
  • Mutagenic activities of extracts from the filtrate of the cultured broth (PI-I), mycelia (pI-II), and the fruiting bodies (PI-III) of Phellinus igniarius were examined by Ames/Salmonella tests. No mutagenic activity was found in Salmonella typhimurium strains TA98 and TA100, either with or without S9 activation. In contrast, PI-I, PI-II, and PI-III showed inhibitory effects on the mutagenic activities by the directly-acting mutagens, 4-nitro-ο-phenylenediamine(NPD) and sodium azide ($NaN_3$), and also by the indirectly-acting mutagens, 2-aminofluorene (2-AF) and benzo[a]pyrene (B[a]P). These results suggest that P. igniarius possesses some antimutagenic activity and may contain some chemopreventive agents.

  • PDF

Design of LQ-servo PI controller considering Weight (가중치를 이용한 LQ-Servo형 PI 제어기 설계)

  • 서병설
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.25 no.3B
    • /
    • pp.570-576
    • /
    • 2000
  • This paper proposed LQ-Servo PI controller by considering LQ-Servo structure as PI controller with a partial state feedback and concerns about the development of the flexible design algorithm by introducing weights to the design parameters of the previous LQ-Servo design method. the propose algorithm improves the matchings of the maximum and minimum singular values at high and low frequencies of the design loop transfer function as well as its loop shaping for performance.

  • PDF

Fault Detection and Isolation of System Using Multiple Pi Observers (비례적분(PI) 관측기를 이용한 시스템의 고장진단)

  • Kim, H.S.;Kim, S.B.;Shigeyasu Kawaji
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.14 no.2
    • /
    • pp.41-47
    • /
    • 1997
  • Fault diagnosis problem is currently a subject of extensive research in the control field. Although there are several works on the fault detection and isolation observers and the residual generators, those are con- cerned with only the detection of actuator failures or sensor failures. So, the perfect detection and isolation for the actuator and sensor failures is strongly required in the field of the practical applications. In this paper, a strategy of fault diagnosis using multiple proportional integral (PI) observers including the magnitude of actuator failures is provided. It is shown that actuator failures are detected and isolated perfectly by monitoring the integrated error between actual output and estimated output by a PI observer. Also in presence of complex actuator and sensor failures, these failures are detected and isolated by multiple PI observers.

  • PDF

Synthesis and Characterization of New Dihydroindolo[3,2-b]indole and 5,6-Bis(octyloxy)-4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole-Based Polymer for Bulk Heterojunction Polymer Solar Cells

  • Kranthiraja, Kakaraparthi;Gunasekar, Kumarasamy;Song, Myungkwan;Gal, Yeong-Soon;Lee, Jae Wook;Jin, Sung-Ho
    • Bulletin of the Korean Chemical Society
    • /
    • v.35 no.5
    • /
    • pp.1485-1490
    • /
    • 2014
  • We have designed and developed a new ladder type tetrafused ${\pi}$-conjugated building block such as dihydroindolo[3,2-b]indole (DINI) and investigated its role as an electron rich unit. The photovoltaic properties of a new semiconducting ${\pi}$-conjugated polymer, poly[[5,10-bisoctyl-5,10-dihydroindolo[3,2-b]indole-[5,6- bis(octyloxy)-4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole]], represented by PDINI-OBTC8 are described. The new polymer PDINI-OBTC8 was synthesized in donor-acceptor (D-A) fashion, where fused ${\pi}$-conjugated tetracyclic DINI, and 5,6-bis(octyloxy)-4,7-di(thiophen-2-yl) benzo[c][1,2,5]thiadiazole (OBTC8) were employed as electron rich (donor) and electron deficient (acceptor) moieties, respectively. The conventional bulk heterojunction (BHJ) device structure ITO/PEDOT:PSS/PDINI-OBTC8:PCB71M/LiF/Al was utilized to fabricate polymer solar cells (PSCs), which comprises the blend of PDINI-OBTC8 and [6,6]-phenyl-$C_{71}$-butyric acid methyl ester ($PC_{71}BM$) in BHJ network. A BHJ PSC that contain PDINI-OBTC8 delivered power conversion efficiency (PCE) value of 1.68% with 1 vol% of 1,8-diidooctane (DIO) under the illumination of A.M 1.5G 100 $mW/cm^2$.

Quantitative Structure-Activity Relationships in MAO-Inhibitor~' 2-Phenylcyclopropylarnines: Insights into the Topography of MAO-A and MAO-B

  • Kang, Gun-Il;Hong, Suk-Kil
    • Archives of Pharmacal Research
    • /
    • v.13 no.1
    • /
    • pp.82-96
    • /
    • 1990
  • Ten (E)-and (Z)-isomers of 2-phenylcyclopropylamine (PCA), 1-Me PCA, 2-Me-PCA, N-Me-PCA, and N, N-diMe PCA and fifteen o-. m-, p- isomers of (E) PCA with substituents of Me, Cl, F, OMe, OH were synthesized in this laboratory and tested for the inhibition of rat brain mitochondrial MAO-A and MAO-B. The effects of substituents, their positions, and stereochemistry on the inhibition were assessed for the compounds with substituents at cyclopropyl and amino groups and QSAR analyses were performed using the potency data of ring-substituted compounds. The best correlated QSAR equations are as follows : pI$_{50}$ = 0.804 $\pi^2$-0.834 Blo-1.069 Blm + 0.334 Lp-1.709 HDp +7.897 (r = 0.945, s =0.211, F = 16.691, p = 0.000) for the inhibition of MAO-A;PI$_{50}$= 1.815$\pi$-0.825 $\pi^2$-1.203R + 0.900 Es$^2$ + 0.869 Es$^3$ + 0.796 Es$^4$-0.992 HDp + 0.562 HAo + 3.893 (r = 0.982, s =0.178, F = 23.351, p = 0.000) for the inhibition of MAO-B. Based on the potency difference between stereoisomers of cyclopropylamine-modified compounds and an QSAR cavity near para position, two hydrophobic carities interacting with Me group, a hydrophobic site near para position, and an amino group binding site and that in addition to the same two hydrophotic cavities, hydrophotic area, steric boundaries, hydrogen-acceptor site, and amino group binding site, another steric boundary near para position and a hydrogen donating site near ortho position constitute active sites of MAO-B.

  • PDF

Critical role of protein L-isoaspartyl methyltransferase in basic fibroblast growth factor-mediated neuronal cell differentiation

  • Dung, To Thi Mai;Yi, Young-Su;Heo, Jieun;Yang, Woo Seok;Kim, Ji Hye;Kim, Han Gyung;Park, Jae Gwang;Yoo, Byong Chul;Cho, Jae Youl;Hong, Sungyoul
    • BMB Reports
    • /
    • v.49 no.8
    • /
    • pp.437-442
    • /
    • 2016
  • We aimed to study the role of protein L-isoaspartyl methyltransferase (PIMT) in neuronal differentiation using basic fibroblast growth factor (bFGF)-induced neuronal differentiation, characterized by cell-body shrinkage, long neurite outgrowth, and expression of neuronal differentiation markers light and medium neurofilaments (NF). The bFGF-mediated neuronal differentiation of PC12 cells was induced through activation of mitogen-activated protein kinase (MAPK) signaling molecules [MAPK kinase 1/2 (MEK1/2), extracellular signal-regulated kinase 1/2 (ERK1/2), and p90RSK], and phosphatidylinositide 3-kinase (PI3K)/Akt signaling molecules PI3Kp110β, PI3Kp110γ, Akt, and mTOR. Inhibitors (adenosine dialdehyde and S-adenosylhomocysteine) of protein methylation suppressed bFGF-mediated neuronal differentiation of PC12 cells. PIMT-eficiency caused by PIMT-specific siRNA inhibited neuronal differentiation of PC12 cells by suppressing phosphorylation of MEK1/2 and ERK1/2 in the MAPK signaling pathway and Akt and mTOR in the PI3K/Akt signaling pathway. Therefore, these results suggested that PIMT was critical for bFGF-mediated neuronal differentiation of PC12 cells and regulated the MAPK and Akt signaling pathways.

Comparative Efficacy of Ivermectin and Levamisole for Reduction of Migrating and Encapsulated Larvae of Baylisascaris transfuga in Mice

  • Fu, Yan;Nie, Hua-Ming;Niu, Li-Li;Xie, Yue;Deng, Jia-Bo;Wang, Qiang;Yang, Guang-You;Gu, Xiao-Bin;Wang, Shu-Xian
    • Parasites, Hosts and Diseases
    • /
    • v.49 no.2
    • /
    • pp.145-151
    • /
    • 2011
  • The comparative efficacy of 2 anthelmintics (ivermectin and levamisole) against Baylisascaris transfuga migrating and encapsulated larvae was studied in mice. A total of 60 BALB/c mice inoculated each with about 1,000 embryonated B. transfuga eggs were equally divided into 6 groups (A-F) randomly. Mice of groups A and B were treated with ivermectin and levamisole, respectively, on day 3 post-infection (PI). Mice of groups A-C were killed on day 13 PI. Similarly, groups D and E were treated with ivermectin and levamisole, respectively, on day 14 PI, and all mice of groups D-F were treated on day 24 PI. The groups C and F were controls. Microexamination was conducted to count the larvae recovering from each mouse. The percentages of reduction in the number of migrating larvae recovered from group A (ivermectin) and B (levamisole) were 88.3% and 81.1%, respectively. In addition, the reduction in encapsulated larvae counts achieved by ivermectin (group D) and levamisole (group E) was 75.0% and 49.2%, respectively. The results suggested that, to a certain extent, both anthelmintics appeared to be more effective against migrating larvae than encapsulated larvae. However, in the incipient stage of infection, ivermectin may be more competent than levamisole as a larvicidal drug for B. transfuga.

Studies on blood types in Thoroughbred horses (더러브렛 말의 혈액형에 관한 연구)

  • Cho, Gil-jae;Kim, Bong-hwan
    • Korean Journal of Veterinary Research
    • /
    • v.40 no.4
    • /
    • pp.683-689
    • /
    • 2000
  • The present study was carried out to investigate the blood markers of Thoroughbred horses (TB) The blood red cell types and blood protein types (biochemical polymorphisms) were tested from 1,125 Thoroughbred horses by serological and electrophoretic procedures, and their phenotypes, gene frequencies, heterozygosity, polymorphic information content values and exclusion probability were estimated. The blood group and biochemical polymorphism phenotypes observed with high frequency were Aaf(91.7%), Ca(94.7%), K-(94.5%), Ua(75.9%), P-(50.6%), Qabc(82.6%), ALB-BB(67.7%), GC-FF(92.7%), AIB-KK(99.6%), ES-II(77.9%), TF-DF1(23.6%), PI-LL(23.2%), HB-B2B2(73.6%), PGD-FS(45.4%) and genotypes Dcgm/dk(16.9%), Dbcm/cgm(13.6%), Dbcm/dk(11.9%), Dcegmn/cegmn(10.0%), Dcgm/cgm(8.7%) in TB. Alleles observed with high frequency were Aaf(0.796), Ca(0.769), Ddk(0.266), Dcgm(0.261), Dbcm(0.211), K-(0.972), P-(0.710), Qabc(0.565), Q-(0.368), Ua(0.509), $HB^{B2}$(0.858), $PGD^F$(0.634), $ALB^B$(0.825), $GC^F$(0.927), $AIB^K$(0.998), $ES^I$(0.881), $TF^{F1}$(0.346), $TF^D$(0.319), $TF^{F2}$(0.184), $PI^L$(0.479), $PI^N$(0.214), $PI^U$(0.116) in TB. The heterozygosity, polymorphic information content (PIC) and exclusion probability (PE) were calculated. The mean heterozygosity and PIC value were 0.3899 and 0.3375, respectively. The highest heterozygosity and PIC were estimated 0.7834 and 0.7492 in blood group D locus, respectively. The cumulated PE obtained by blood groups and biochemical polymorphisms was 0.9813.

  • PDF

Carbonylative Cyclization of Unsaturated Carboxylic Acids by Palladium Complexes with Phosphines(II) Theoretical Studies on Palladium(0, II) Complexes of Unsaturated Carboxylic Acids (포스핀류가 배위된 팔라듐 착물에 의한 불포화카르복실산의 카르보닐화고리 반응 (제 2 보). 불포화카르복실산이 배위된 팔라듐 (0, II) 착물에 관한 이론적 연구)

  • Doh Myung-Ki;Bong-Gon Kim;Maeng-Jun Jung;Young-Dae Song;Byung-Kak Park
    • Journal of the Korean Chemical Society
    • /
    • v.37 no.4
    • /
    • pp.431-441
    • /
    • 1993
  • The structure and reactivity of ${\pi}$-and metallacycle form in the bis(trimethylphosphine) palladium(0) complexes with acrylic acid, methacrylic acid, crotonic acid(A group) and 3-butenoic acid, 4-pentenoic acid(B group) have been investigated by Molecular Mechanics and Extended Huckel Molecular Orbital method. The calculation shows that A groups with large value of frontier electron density of HOMO and LUMO produce $\pi-complexes$ instead of metallacycle. But B groups with small value of frontier electron density of LUMO, especially 3-butenoic acid, form stable metallacycle. Moreover the methyl-substituted five-membered compared with the six-membered metallacycle is energetically stable conformation.

  • PDF

A $\pi$-type Variable Attenuator with Low Phase Shift (저위상 변화 특성을 갖는 $\pi$-형 가변 감쇠기)

  • Park, Ung-Hee;Ahn, Gil-Cho
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.13 no.10
    • /
    • pp.2066-2070
    • /
    • 2009
  • A voltage controlled attenuator using a PIN diode and two resistors of the $\pi$-type fixed attenuator is described in this paper. The proposed variable attenuator operating for a fixed attenuation range has a good input VSWR and a low intermodulation signal. For the low phase shift, a PIN diode is connected with open stub for the purpose of phase compensation. The stub for phase compensation is calculated by the Deloach method and the related circuit theory. This attenuator is easily fabricated on the microstrip and can be normally used in fine control circuits within small attenuation range. The fabricated attenuator for 2110~2170 MHz frequency band has about 4 dB of an attenuation range, $2^{\circ}$ of phase variance, and -20 dB of S11 according to the input voltage from 0 to 2.7 V.