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61.
Abbott B Abbott R Adhikari R Agresti J Ajith P Allen B Allen J Amin R Anderson SB Anderson WG Araya M Armandula H Ashley M Aulbert C Babak S Balasubramanian R Ballmer S Barish BC Barker C Barker D Barton MA Bayer K Belczynski K Betzwieser J Bhawal B Bilenko IA Billingsley G Black E Blackburn K Blackburn L Bland B Bogue L Bork R Bose S Brady PR Braginsky VB Brau JE Brown DA Buonanno A Busby D Butler WE Cadonati L Cagnoli G Camp JB Cannizzo J Cannon K Cardenas L Carter K Casey MM Charlton P 《Physical review letters》2005,95(22):221101
The Laser Interferometer Gravitational-Wave Observatory has performed a third science run with much improved sensitivities of all three interferometers. We present an analysis of approximately 200 hours of data acquired during this run, used to search for a stochastic background of gravitational radiation. We place upper bounds on the energy density stored as gravitational radiation for three different spectral power laws. For the flat spectrum, our limit of omega0 < 8.4 x 10(-4) in the 69-156 Hz band is approximately 10(5) times lower than the previous result in this frequency range. 相似文献
62.
G. R. Nalin Rathnayake N. Savitri Kumar Hiroshi Araya Yoshinori Fujimoto 《Natural product research》2018,32(20):2483-2486
Phialemonium curvatum, an endophytic fungus isolated from the leaves of Passiflora edulis was cultured in potato dextrose broth (PDB) media and chromatographic separation of the EtOAc extract of the broth and mycelium led to the isolation of 4-hydroxybenzoic acid (1), 3-indole acetic acid (2), solaniol (3), uracil (4), uridine (5) and glycerol (6). Compound 2 showed a weak antifungal activity against Cladosporium cladosporioides. This is the first report of the isolation of the endophytic fungus P. curvatum from P. edulis and complete 13CNMR assignments of 3. 相似文献
63.
NCA0424 (1) and its side chain positional isomer, NCA0465 (2), are indoloquinoxaline derivatives with potent antitumor activity. To investigate the effect of side chain position for binding with DNA, the interactions of 2 with various B-form DNAs were studied by spectroscopic (circular dichroism (CD), fluorescence and UV) and viscosity measurements and were compared with those of 1. The binding preference for the base sequence was different in each case. The CD spectra showed that 2 formed an asymmetric binding of indoloquinoxaline ring with adenine in DNA, whereas such a base selectivity was not found with 1. The binding features are discussed based on association constants and thermodynamic parameters, indicating the importance of the side chain position for binding specificity for DNA. 相似文献
64.
Carbonell T Masip I Sánchez-Baeza F Delgado M Araya E Llorens O Corcho F Pérez JJ Pérez-Payá E Messeguer A 《Molecular diversity》2000,5(3):131-143
The potentiation of central cholinergic activity has been proposed as a therapeutic approach for improving cognitive function in patients with Alzheimer's disease. Increasing the acetylcholine concentration in brain by modulating acetylcholinesterase (AChE) activity is among the most promising strategies. We have used a combinatorial approach to identify different 2,5-piperazinediones (DKP) with AChE inhibitory activity. Our goal was to find inhibitors exhibiting high AChE/BuChE (butyrylcholinesterase) selectivity, in order to reduce the undesirable side effects elicited by most of the inhibitors that have been developed to date. Screening of a DKP library constructed on solid-phase using the multiple parallel synthesis format, resulted in the identification of several compounds with moderate efficacy on AChE. In particular, DKP-80 had an IC50 = 2.2 microM with no significant inhibitory activity on BuChE. Moreover, estimated values of Clog P and log BB for the most active compounds fulfilled the bioavailability requirements for enzyme inhibitors acting on the central nervous system. In order to understand the inhibitory properties of the ligand at the molecular level, molecular dynamics simulations were computed on DKP-80 complexed to AChE, and the most relevant binding interactions of this inhibitor to the active center of the enzyme were characterized. Overall the present results indicate that the DKP-based compounds identified are novel AChE inhibitors which may be considered likely lead compounds for further development of drug candidates against Alzheimer's disease. 相似文献
65.
Araya Y Kasuga J Toyota K Hirakawa Y Oyama T Makishima M Morikawa K Hashimoto Y Miyachi H 《Chemical & pharmaceutical bulletin》2008,56(9):1357-1359
Based on the result of X-ray crystallographic analysis of our peroxisome proliferator-activated receptor alpha and delta (PPARalpha/delta) co-agonist complexed with human PPAR ligand binding domain (LBD), we designed and synthesized an optically active fluorescent PPARalpha/delta co-agonist, which has a pyrene unit incorporated directly at the hydrophobic tail part of the structure as a fluorophore. This fluorescent co-agonist was applied in a homogeneous fluorescent polarization assay format for the identification of PPARdelta ligands. 相似文献
66.
The dynamics of [Zn(D2O)6]2+ in [Zn(D2O)6][SiF6] was investigated by 2H NMR one-dimensional spectra, two-dimensional exchange spectra and spin-lattice relaxation time (T1). The lineshapes of those spectra and T1 were dominated by the 180° flip of the water molecules and the reorientation of [Zn(D2O)6]2+ about the C3 axis. The variation of lineshape of the one-dimensional spectrum below room temperature can be explained by only the 180° flip of the water molecules. The spectrum at room temperature showed a typical shape due to the rapid 180° flip of water molecules. The change in lineshape of the one-dimensional 2H NMR spectrum is caused by the three-site jump of [Zn(D2O)6]2+ about its C3 axis above 333 K. Information of the reorientation of [Zn(D2O)6]2+ below 333 K could not be obtained from the one-dimensional spectrum and T1. In this temperature range, the two-dimensional exchange spectrum was effective for analysis of molecular motion. The effects of multiple motions, the 180° flip of the water molecules and the reorientation of [Zn(D2O)6]2+ about the C3 axis, on the lineshape of the two-dimensional exchange spectrum were studied using spectral simulation. 相似文献
67.
We consider a -parameter Hermite process with Hurst index and we study its limit behavior in distribution when the Hurst parameters (or a part of them) converge to and/or 1. The limit obtained is Gaussian (when at least one parameter tends to ) and non-Gaussian (when at least one-parameter tends to 1 and none converges to ). 相似文献
68.
We employ numerically implicit subgrid-scale modeling provided by the well-known streamlined upwind/Petrov–Galerkin stabilization for the finite element discretization of advection–diffusion problems in a Large Eddy Simulation (LES) approach. Whereas its original purpose was to provide sufficient algorithmic dissipation for a stable and convergent numerical method, more recently, it has been utilized as a subgrid-scale (SGS) model to account for the effect of small scales, unresolvable by the discretization. The freestream Mach number is 2.5, and direct comparison with a DNS database from our research group, as well as with experiments from the literature of adiabatic supersonic spatially turbulent boundary layers, is performed. Turbulent inflow conditions are generated via our dynamic rescaling–recycling approach, recently extended to high-speed flows. Focus is given to the assessment of the resolved Reynolds stresses. In addition, flow visualization is performed to obtain a much better insight into the physics of the flow. A weak compressibility effect is observed on thermal turbulent structures based on two-point correlations (IC vs. supersonic). The Reynolds analogy ( vs. ) approximately holds for the supersonic regime, but to a lesser extent than previously observed in incompressible (IC) turbulent boundary layers, where temperature was assumed as a passive scalar. A much longer power law behavior of the mean streamwise velocity is computed in the outer region when compared to the log law at Mach 2.5. Implicit LES has shown very good performance in Mach 2.5 adiabatic flat plates in terms of the mean flow (i.e., and ). iLES significantly overpredicts the peak values of , and consequently Reynolds shear stress peaks, in the buffer layer. However, excellent agreement between the turbulence intensities and Reynolds shear stresses is accomplished in the outer region by the present iLES with respect to the external DNS database at similar Reynolds numbers. 相似文献
69.
It is known that all doubly‐even self‐dual codes of lengths 8 or 16, and the extended Golay code, can be constructed from some binary Hadamard matrix of orders 8, 16, and 24, respectively. In this note, we demonstrate that every extremal doubly‐even self‐dual [32,16,8] code can be constructed from some binary Hadamard matrix of order 32. © 2004 Wiley Periodicals, Inc. 相似文献
70.
Kwankamol Sastraruji Thanapat Sastraruji Alison T. Ung Renate Griffith Araya Jatisatienr Stephen G. Pyne 《Tetrahedron》2012,68(35):7103-7115
Thirty-two new stemofoline analogues were prepared from didehydrostemofoline for studies as AChE inhibitors. C-3 Side-chain modified amino, carbamate, triazole and oxazole stemofoline derivatives were prepared. In general the amine derivatives were found to be stronger inhibitors of AChE than their alcohol analogues that we previously reported. Compounds 5 and 26, with small C-3 side-chain substituents, were two of the most active inhibitors. Preliminary molecular docking studies suggested that these compounds may inhibit AChE by binding horizontally along the passage of the active-site gorge and block access to acetylcholine. 相似文献