22,335 research outputs found
Exact Maximum Likelihood estimation for the BL-GARCH model under elliptical distributed innovations
No full textIn this paper, we discuss the class of Bilinear GATRCH (BL-GARCH) models which are capable of capturing simultaneously two key properties of non-linear time series : volatility clustering and leverage effects. It has been observed often that the marginal distributions of such time series have heavy tails ; thus we examine the BL-GARCH model in a general setting under some non-Normal distributions. We investigate some probabilistic properties of this model and we propose and implement a maximum likelihood estimation (MLE) methodology. To evaluate the small-sample performance of this method for the various models, a Monte Carlo study is conducted. Finally, within-sample estimation properties are studied using S&P 500 daily returns, when the features of interest manifest as volatility clustering and leverage effects.BL-GARCH process, elliptical distribution, leverage effects, Maximum Likelihood, Monte Carlo method, volatility clustering.
Mean ΔCq values (± standard deviation) of miRNAs from HBsAg particles per groups in Peg-IFN treated patients and inactive carriers [NR-BL (A); NR-Post-T-FU (B); REL BL (C); REL-Post-T-FU (D); SVR BL (E); SVR-Post-T-FU (F); IC (G); NR, REL, SVR BL and REL/NR Post-T-FU (H)].
No full text<p>On the right comparisons between groups F and E; G and E; F and H; G and H.</p><p>Mean ΔCq values (± standard deviation) of miRNAs from HBsAg particles per groups in Peg-IFN treated patients and inactive carriers [NR-BL (A); NR-Post-T-FU (B); REL BL (C); REL-Post-T-FU (D); SVR BL (E); SVR-Post-T-FU (F); IC (G); NR, REL, SVR BL and REL/NR Post-T-FU (H)].</p
Many-electron theory of resonant charge transfer: Role of surface states in He and He+ scattering off Si(100)
No full textA many-electron theory of resonant charge transfer, originally formulated for the scattering of an atom with an empty valence orbital from a surface, is extended to treat the case where the valence orbital is initially occupied by one or two electrons. The scattering of He and He+ from the Si(001) surface is investigated. The interaction is assumed to be with the narrow band of surface states, and not the much wider bulk band. As a result, considerable oscillations are found in the ionization and/or neutralization probabilities as a function of the incident energy.PT: J; CR: AMOS AT, 1989, ADV CHEM PHYS, V76, P335 AMOS AT, 1989, SOLID STATE COMMUN, V71, P449 BLOSS W, 1978, SURF SCI, V72, P277 BRAKO R, 1981, SURF SCI, V108, P253 BURROWS BL, 1984, Q APPL MATH, V42, P73 BURROWS BL, 1990, J PHYS A-MATH GEN, V23, P1101 BURROWS BL, 1991, SURF SCI, V253, P365 CHADI DJ, 1975, PHYS STATUS SOLIDI B, V68, P405 HAGSTRUM HD, 1954, PHYS REV, V96, P336 HAGSTRUM HD, 1961, PHYS REV, V122, P83 HERMAN F, 1963, ATOMIC STRUCTURE CAL IHM J, 1980, PHYS REV B, V21, P4592 MUDA Y, 1980, SURF SCI, V97, P283 MUDA Y, 1988, NUCL INSTRUM METH B, V33, P388 MUDA Y, 1988, PHYS REV B, V37, P7048 PAULING L, 1935, INTRO QUANTUM MECHAN ROBERTS N, 1990, SURF SCI, V236, P112 SOUDA R, 1985, SURF SCI, V150, L59 SOUDA R, 1986, NUCL INSTRUM METH B, V15, P114 SOUDA R, 1986, NUCL INSTRUM METH B, V15, P138 SOUDA R, 1986, SURF SCI, V176, P657 SULSTON KW, 1988, PHYS REV B, V37, P9121 SULSTON KW, 1988, SURF SCI, V197, P555 SULSTON KW, 1989, SURF SCI, V244, P543 WEAKLIEM PC, 1990, SURF SCI, V232, L219 WEISENDANGER R, 1990, SURF SCI, V232, P1; NR: 26; TC: 4; J9: PHYS REV B; PG: 11; GA: HZ245Source type: Electronic(1
Luteolin inhibited clade B and –C Tat–mediated LTR transactivation in TZM-bl reporter cells.
No full text<p>(<b>A</b>) TZM-bl reporter cells were transfected with Tat expression vector (pcDNA-Tat) and treated after 4 h with different concentrations of either luteolin (0–10 µM) or vehicle and monitored for luciferase activity. (<b>B</b>) TZM-bl cells were transfected with pIRES2-EGFP-Tat-HA (400 ng) and, 24 h later, treated with 0-, 5- and 10- µM luteolin. A Tat-specific siRNA cocktail of 3 siRNAs (300 nM) was co-transfected with Tat expression vector as a positive control. 48 h post-transfection, cells were harvested for Western blot using anti-HA and anti-β actin antibody. (<b>C</b>) TZM-bl cells transfected with HIV-1 subtype-B or -C Tat expression vectors (pcDNA-Tat) were treated with luteolin (10 µM) at 4 h after transfection. In parallel, mutant Tat-47 (Δ 47–56 aa) was used as a negative control. LTR luciferase activity was assessed at 48 h after transfection. Protein levels expressed from Tat expression vectors were monitored by Western blot with anti-HA and anti-β-actin antibody. *** p<0.001. (<b>D</b>) Effect of luteolin treatment on subcellular localization of Tat protein in HeLa cells. Immunostaining showing subcellular localization of Tat protein in HeLa cells after treatment with luteolin (10 µM), DMSO as a vehicle control (DMSO), or untreated (-). IgG was used as isotype antibody control (Isotype). Cells were immunostained for Tat (red), B23/nucleophosmin (green), and nuclei (blue), images were captured at 20× with a Nikon fluorescent microscope.</p
Epithelial proliferation in response to <i>H</i>. <i>pylori</i> infection of C57BL/6 (BL/6) and CD44 deficient (CD44KO) mice.
No full text<p>Stomach sections collected from (<b>A</b>) uninfected BL/6 control, (<b>B</b>) <i>H</i>. <i>pylori</i> infected BL/6, (<b>C</b>) ∆CagA <i>H</i>. <i>pylori</i> strain infected BL/6, and (<b>D</b>) uninfected and (<b>E</b>) <i>H</i>. <i>pylori</i> infected CD44KO mice were immunostained for BrdU incorporation (blue nuclei). (<b>F</b>) Quantification of BrdU+ cells/gland in each group. *P<0.05 compared to controls, n = 6 mice per group.</p
Generalized measures for physical properties of nonperiodic chains
No full textPT: J; CR: AVISHAI Y, 1990, PHYS REV B, V41, P5492 BORN M, 1965, PRINCIPLES OPTICS BURROWS BL, 1991, J PHYS A-MATH GEN, V24, P3979 DAVISON SG, 1992, BASIC THEORY SURFACE GUMBS G, 1989, J PHYS A-MATH GEN, V22, P951 KIANG D, 1990, AM J PHYS, V58, P1200 KOHMOTO M, 1987, PHYS REV LETT, V58, P2436 KOLAR M, 1991, PHYS REV B, V43, P1034 PATTNAIK RK, 1992, J PHYS A-MATH GEN, V25, P577 THAKUR PK, 1992, J PHYS-CONDENS MAT, V4, P6095; NR: 10; TC: 5; J9: PHYS REV B; PG: 7; GA: QL717Source type: Electronic(1
Subtype B neutralization in A3R5 cells and TZM-bl.
No full text<p><b>A</b>-<b>C</b>. <b>Neutralization sensitivity of three tier 2 subtype B IMC.LucR transmitted/founder viruses to sCD4 and a panel of four mAbs in two A3R5 cell lines and TZM-bl</b>. With the exception where no inhibition was noted for any cell line, the A3R5 cell lines showed greater neutralization for all inhibitors tested compared to TZM-bl. <b>D</b>. <b>Grouped inhibitor comparison between cell lines</b>. When grouped by cell line using the non-parametric Mann-Whitney test, there was a significant difference between the A3R5 cell lines and TZM-bl (Mann-Whitney test; p<0.001). IC50 titers are the concentration of inhibitor at which the Renilla luciferase signal (RLUs) was reduced by 50% compared to the virus control (no inhibitor). Inhibitor concentrations ranged from 0.78 μg/mL to 25 μg/mL. All assays were performed in the presence of DEAE-Dextran.</p
Scanning tunneling microscope imaging technique for weakly bonded surface deposits
No full textPT: J; CR: BLACKFORD BL, IN PRESS J MICROSC BLACKFORD BL, 1987, REV SCI INSTRUM, V58, P1343 FOSTER JS, IN PRESS J MICROSC GUCKENBERGER R, 1988, ULTRAMICROSCOPY, V25, P111 HANSMA PK, 1987, J APPL PHYS, V61, R1 MAMIN HJ, 1986, PHYS REV B, V34, P9015 SMITH D, IN PRESS J MICROSC; NR: 7; TC: 24; J9: J APPL PHYS; PG: 3; GA: U7926Source type: Electronic(1
BL-dependent H<sup>+</sup>-pumping enhanced by RL-activated guard cell photosynthesis.
No full text<p>A–C. H<sup>+</sup>-pumping induced by the irradiation with BL with (B and C, [R55+B5]) or without RL irradiation (A, [B5]) in wild-type guard cell protoplasts. Guard cell protoplasts (50 µg protein) were irradiated with 5 µmol m<sup>−2</sup> s<sup>−1</sup> BL with or without 2 to 3 h pre-irradiation and background irradiation with 55 µmol m<sup>−2</sup> s<sup>−1</sup> RL. DCMU (dissolved in DMSO) was administered to the protoplasts before pre-irradiation with RL at a final concentration of 10 µM (0.01% DMSO) (C). D, Maximum rates of H<sup>+</sup>-pumping by guard cell protoplasts under different light conditions as in A to C. Data represent means ± SD of three independent experiments. E–I. pH changes induced by irradiation with BL or RL in wild-type (E, G, and I) and <i>phot1phot2</i> (F and H) guard cell protoplasts. Guard cell protoplasts (50 µg protein) were dark-adapted for 1 h before 5 µmol m<sup>−2</sup> s<sup>−1</sup> BL (E, F, and I [B5]) or 60 µmol m<sup>−2</sup> s<sup>−1</sup> RL (G and H [R60]) was applied where indicated by arrows. DCMU was administered before dark-adaptation at 10 µM (I).</p
Interactions between drought, ABA application and supplemental UV-B in Populus yunnanensis
No full textTo test whether drought and ABA application alter the effects of enhanced UV-B on the growth and biomass allocation of Populus yunnanensis Dode, cuttings were grown in pots at two ABA levels, two watering regimes and two UV-B levels for one growth season. Exposure to enhanced UV-B radiation significantly decreased plant growth and photosynthesis under well-watered conditions, but these effects were obscured by drought, which alone caused growth reduction. Drought may contribute to masking the effects of UV-B radiation. The accumulation of UV-B absorbing compounds and the increase of the ABA content induced by drought could reduce the effectiveness of UV-B radiation. ABA application did not have large direct effects on biomass accumulation and allocation. Evidence for interactions between UV-B and ABA was detected for only a few measured traits. Therefore, there was little evidence to support a pivotal role for ABA in regulating a centralized whole plant response to enhanced UV-B. Yet, we recorded an ABA-induced decrease in stomatal conductance (g(s)) and increase in UV-B absorbing compounds and carbon isotope composition (delta C-13) in response to enhanced UV-B. The allometric analysis revealed that regression models between root and shoot biomass in response to enhanced UV-B are different for plants under well-watered and drought conditions. Enhanced UV-B led to a significant displacement of the allometric regression line under well-watered condition, while allometric trajectories for both UV-B regimes did not differ significantly under drought condition
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