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Background
Recently several studies have shown that people use contextual information to make predictions about the rest of the sentence or story as the text unfolds. Using event related potentials (ERPs) we tested whether these on-line predictions are based on a message-level representation of the discourse or on simple automatic activation by individual words. Subjects heard short stories that were highly constraining for one specific noun, or stories that were not specifically predictive but contained the same prime words as the predictive stories. To test whether listeners make specific predictions critical nouns were preceded by an adjective that was inflected according to, or in contrast with, the gender of the expected noun. 相似文献95.
Alvarez M Carrascosa LG Moreno M Calle A Zaballos A Lechuga LM Martínez-A C Tamayo J 《Langmuir : the ACS journal of surfaces and colloids》2004,20(22):9663-9668
Biomolecular interactions over the surface of a microcantilever can produce its bending motion via changes of the surface stress, which is referred to nanomechanical response. Here, we have studied the interaction forces responsible for the bending motion during the formation of a self-assembled monolayer of thiolated 27-mer single-stranded DNA on the gold-coated side of a microcantilever and during the subsequent hybridization with the complementary nucleic acid. The immobilization of the single-stranded DNA probe gives a mean surface stress of 25 mN/m and a mean bending of 23 nm for microcantilevers with a length and thickness of about 200 microm and 0.8 microm, respectively. The hybridization with the complementary sequence could not be inferred from the nanomechanical response. The nanomechanical response was compared with data from well-established techniques such as surface plasmon resonance and radiolabeling, to determine the surface coverage and study the intermolecular forces between neighboring DNA molecules anchored to the microcantilever surface. From both techniques, an immobilization surface density of 3 x 10(12) molecules/cm(2) and a hybridization efficiency of 40% were determined. More importantly, label-free hybridization was clearly detected in the same conditions with a conventional sensor based on surface plasmon resonance. The results imply that the nanomechanical signal during the immobilization process arises mainly from the covalent attachment to the gold surface, and the interchain interactions between neighboring DNA molecules are weak, producing an undetectable surface stress. We conclude that detection of nucleic acid hybridization with nanomechanical sensors requires reference cantilevers to remove nonspecific signals, more sensitive microcantilever geometries, and immobilization chemistries specially addressed to enhance the surface stress variations. 相似文献
96.
A two-photon laser-induced fluorescence study on the transport of ground-state atomic hydrogen in a supersonic plasma jet, generated from an Ar-H (2) mixture, reveals an unexpected shock pattern. Whereas both the axial-velocity profile and the temperature profile of hydrogen atoms along the jet centerline can be interpreted in terms of a supersonic expansion of an Ar-H gas mixture, the H-atom density profiles do not satisfy the well established Rankine-Hugoniot relation leading to a nonconservation of the forward flux. The experimental results show that H atoms escape from the supersonic expansion by a diffusion process due to strong density gradients between the core of the jet and its vicinity. 相似文献
97.
Tamayo A Pedras B Lodeiro C Escriche L Casabó J Capelo JL Covelo B Kivekäs R Sillanpää R 《Inorganic chemistry》2007,46(19):7818-7826
The complexation properties toward Hg(II) of six macrocyclic ligands, 3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L1), 7-(9-anthracenylmethyl)-3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L2), 7-(10-methyl-9-anthracenylmethyl)-3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L3), 7,7'-[9,10-anthracenediylbis(methylene)]bis-3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L4), 1,4,7-trithia-11-azacyclotetradecane (L5), and 11,-(anthracen-9-ylmethyl)-1,4,7-trithia-11-azacyclotetradecane (L6), were studied. The stoichiometries of the formed species were determined from absorption and fluorescence titrations. In these anthracene-containing macrocycles, a fluorescent quenching of the emission was found upon Hg(II) addition. The X-ray crystal structure of [HgCl2(L2)] x 1/2CH2Cl2 was determined. The asymmetric unit contains two independent [HgCl2(L2)] molecules and one dichloromethane molecule. Each Hg(II) ion is coordinated by the pyridine nitrogen, the two sulfur atoms of one L2 molecule, and two chloride ions. Analytical studies using solvent extraction separation of Hg(II) from aqueous solutions were performed to determine the Hg(II) extraction capability of ligands L1, L2, and L5. 相似文献
98.
Tamayo A Casabó J Escriche L González P Lodeiro C Rizzi AC Brondino CD Passeggi MC Kivekäs R Sillanpää R 《Inorganic chemistry》2007,46(14):5665-5672
The properties of Cu(II) and Co(II) complexes with oxygen- or nitrogen-containing macrocycles have been extensively studied; however, less attention has been paid to the study of complexes containing sulfur atoms in the first coordination sphere. Herein we present the interaction between these two metal ions and two macrocyclic ligands with N2S2 donor sets. Cu(II) and Co(II) complexes with the pyridine-containing 14-membered macrocycles 3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L) and 7-(9-anthracenylmethyl)-3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L1) have been synthesized. The X-ray structural analysis of {[Co(ClO4)(H2O)(L)][Co(H2O)2(L)]}(ClO4)3 shows two different metal sites in octahedral coordination. The EPR spectra of powdered samples of this compound are typical of distorted six-coordinated Co(II) ions in a high-spin (S=3/2) configuration, with the ground state being S=1/2 (g1=5.20, g2=3.20, g3=1.95). The EPR spectrum of [Cu(ClO4)(L)](ClO4) was simulated assuming an axial g tensor (g1=g2=2.043, g3=2.145), while that of [Cu(ClO4)(L1)](ClO4) slightly differs from an axial symmetry (g1=2.025, g2=2.060, g3=2.155). These results are compatible with a Cu(II) ion in square-pyramidal coordination with N2S2 as basal ligands. Single-crystal EPR experiment performed on [Cu(ClO4)(L1)](ClO4) allowed determining the eigenvalues of the molecular g tensor associated with the copper site, as well as the two possible orientations for the tensor. On the basis of symmetry arguments, an assignment in which the eigenvectors are nearly along the Cu(II)-ligand bonds is chosen. 相似文献
99.
Paula A. Zapata Laura Tamayo Maritza Páez Enrique Cerda Ignacio Azócar Franco M. Rabagliati 《European Polymer Journal》2011,47(8):1541-1549
Polyethylene nanocomposites containing silver nanoparticles with antimicrobial properties were produced via in situ polymerization. The silver nanoparticles were added together with the catalytic system (metallocene catalyst and methylaluminoxane, MAO, as cocatalyst) directly to the reactor. The polymerization activity did not present significant changes with the incorporation of the silver nanoparticles in comparison to the homopolymerization without filler. The effect of various silver nanoparticle contents on silver ion release and antimicrobial efficacy against Escherichia Coli were studied. Nanocomposites containing higher nanosilver concentrations (5 wt.%) showed the highest silver ion release, and after 24 h reached 99.99% of efficacy against the bacteria compared with the neat PE. Transmission electron microscopy (TEM) images showed that the nanospheres were well dispersed throughout the polyethylene matrix. 相似文献
100.
Hiroshi Nakazawa Tamayo Okahira Takeshi Ishiyama Katsuhiko Miyoshi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8-9)
The reaction of Cp anion, [C 5 H 4 CH 2 CH 2 P(TMS)Mes] m with (CH 3 CN) 3 Mo(CO) 3 leads to the formation of [( m 5 --C 5 H 4 CH 2 CH 2 --P(TMS)Mes)Mo(CO) 3 ] m , which then reacts with MeI to give a metallaphosphacyclopropane complex with silyl migration. 相似文献