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151.
V D'Atri G Oliviero J Amato N Borbone S D'Errico L Mayol V Piccialli S Haider B Hoorelbeke J Balzarini G Piccialli 《Chemical communications (Cambridge, England)》2012,48(76):9516-9518
This communication reports on the synthesis and biophysical, biological and SAR studies of a small library of new anti-HIV aptamers based on the tetra-end-linked G-quadruplex structure. The new aptamers showed EC(50) values against HIV-1 in the range of 0.04-0.15 μM as well as affinities for the HIV-1 gp120 envelope in the same order of magnitude. 相似文献
152.
Dr. Luciano Cuesta Dr. Tatiana Soler Dr. Esteban P. Urriolabeitia 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(47):15178-15189
Novel cycloruthenated complexes 2 a – c , 4 a – c , and 6 a, b based on heteroaromatic cores have been synthesized by reaction of a series of heterocycle‐based imines with [{RuCl(η6‐p‐cymene)}2(μ? Cl)2] and Cu(OAc)2. This approach has proved efficient for the cyclometalation of thiophene, benzothiophene, furan, benzofuran, pyrrole, and indole derivatives. In addition, even a double cyclometalation process over the same heterocyclic ring is possible, yielding unprecedented bimetallic complexes. These ruthenacycles react with 3‐hexyne through an unexpected pathway, which involves the coupling of the original imino heterocycle and acetylene followed by dearomatization to afford fused hetero‐hydropyridyl ligands bonded to the {Ru(p‐cymene)} organometallic moiety (i.e., 7 a – c and 8 a – c ). These complexes represent, as far as we know, the first examples of this type of compound within the context of cyclometalation, and an exhaustive analysis of their structure was carried out in solution and solid state. Furthermore, these unique species react with CuCl2, which promotes the rearomatization and the release of highly valuable aromatic fused bis‐heterocycles (i.e., 9 a – c , 10 a – c, 11 a , and 12 a/12 a′ ), providing a novel and appealing synthetic route to this extraordinary family of molecules. 相似文献
153.
Manca F Giordano S Palla PL Zucca R Cleri F Colombo L 《The Journal of chemical physics》2012,136(15):154906
Stretching experiments on single molecules of arbitrary length opened the way for studying the statistical mechanics of small systems. In many cases in which the thermodynamic limit is not satisfied, different macroscopic boundary conditions, corresponding to different statistical mechanics ensembles, yield different force-displacement curves. We formulate analytical expressions and develop Monte Carlo simulations to quantitatively evaluate the difference between the Helmholtz and the Gibbs ensembles for a wide range of polymer models of biological relevance. We consider generalizations of the freely jointed chain and of the worm-like chain models with extensible bonds. In all cases we show that the convergence to the thermodynamic limit upon increasing contour length is described by a suitable power law and a specific scaling exponent, characteristic of each model. 相似文献
154.
Ana Paula F. Albers Thomaz A. G. Restivo Luciano Pagano Joo B. Baldo 《Thermochimica Acta》2001,370(1-2):111-118
Several experimental techniques either under steady state or transient heat transfer conditions, have been developed to evaluate thermal conductivity and thermal diffusivity of materials. However, testing difficulties resulting from specimen size, extended testing time and heat losses, have somewhat impaired the applicability of many of them. In this respect, the use of the laser flash technique for thermal diffusivity measurements, is a very convenient alternative, considering its basic modeling equation is independent of the temperature gradient as well as the heat flow, and in addition the heat losses can be analytically treated. Another important advantage of the technique is its rapid experimental execution. In this work, it is presented as an investigation concerning how the testing conditions such as specimen coating, laser power and pulse duration, base line adoption, heat losses correction methods, and specimen thickness, may affect the thermal diffusivity measurements of some ceramic materials using the laser flash technique. 相似文献
155.
156.
Matteoli Enrico Lepori Luciano Porcedda Silvia 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2409-2420
Journal of Thermal Analysis and Calorimetry - Excess molar volumes, VE, of binary mixtures of dibromomethane (DBM) with n-hexane, n-heptane, n-octane, cyclohexane, tetrachloromethane, dipropyl and... 相似文献
157.
Diogo Alexandre Siebert Flávia de Mello Michele Debiasi Alberton Luciano Vitali 《Natural product research》2020,34(18):2683-2688
AbstractAlzheimer’s disease and diabetes mellitus are contemporary diseases of great concern. Phenolic compounds are linked to several health benefits and could lead to novel strategies to combat these ailments. The objective of this study was to evaluate by electrophoretically-mediated microanalysis the potential inhibitory activity of the fruit juices from Plinia cauliflora (“jaboticaba”) and Eugenia uniflora (“pitanga”) toward acetylcholinesterase (AChE) and α-glucosidase, target enzymes in strategies for the treatment of these diseases. The phenolic profiles of the samples were also investigated. Jaboticaba and pitanga juices inhibited 85.90?±?1.73 and 52.67?±?1.24% of AChE activity at 5?mg mL?1, and 57.91?±?2.60 and 69.47?±?2.89% of α-glucosidase activity at 1?mg mL?1, respectively. Total phenolic content of the juices were 303.54?±?28.28 and 367.00?±?11.42 mgGA L?1, respectively. The observed inhibitory activity can be explained, at least in part, by the presence of the phenolic compounds. 相似文献
158.
159.
Improving estimation in speckled imagery 总被引:2,自引:0,他引:2
Klaus L. P. Vasconcellos Alejandro C. Frery Luciano B. Silva 《Computational Statistics》2005,20(3):503-519
We propose an analytical bias correction for the maximum likelihood estimators of theG
1
0
distribution. This distribution is a very powerful tool for speckled imagery analysis, since it is capable of describing a
wide range of target roughness. We compare the performance of the corrected estimators with the corresponding original version
using Monte Carlo simulation. This second-order bias correction leads to estimators which are better from both the bias and
mean square error criteria. 相似文献
160.