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31.
Guido Barone Bruno Bove Giuseppina Castronuovo Vittorio Elia 《Journal of solution chemistry》1981,10(11):803-809
The excess enthalpies of aqueous solutions of nine polyols were determined at 25°C and reported in the virial form. The most interesting and new feature of this family of solutes is that the sign of the enthalpic pair interaction coefficients hxx is positive for the first members of the series and negative for the higher homologues. Other points are the large differences found among the values of hxx for stereoisomers, whereas pairs of enantiomers show the same values within experimental errors. An application of the group additivity method is also discussed. 相似文献
32.
Development of a chemiluminescent ELISA and a colloidal gold-based LFIA for TNT detection 总被引:1,自引:0,他引:1
S. Girotti S. Eremin A. Montoya M. J. Moreno P. Caputo M. D’Elia L. Ripani F. S. Romolo E. Maiolini 《Analytical and bioanalytical chemistry》2010,396(2):687-695
To identify the explosive used in a terrorist attack, or to obtain an early sign of environmental pollution it is important
to use simple and rapid assays able to detect analytes at low levels, possibly on-site. This is particularly true for TNT
(2,4,6-trinitrotoluene), one of the most employed explosives in the 20th century and at the same time, because of its toxicity,
a well known pollutant. In this work we describe the development of an indirect competitive ELISA with chemiluminescent detection
(CL-ELISA) and of a lateral-flow immunoassay (LFIA) based on colloidal gold nanoparticle labels. A commercially available
monoclonal antibody was used and 13 specially synthesized conjugates were tested. We optimized the assay by determining the
optimal concentration of monoclonal antibody and conjugates and the influence of various non-specific factors such as: tolerance
to organic solvents at different concentrations, the washing and competitive step time, and the cross-reactivity with related
compounds. The sensitivity and reproducibility of the CL-ELISA were good (LOD and IC50 values in the ng mL−1 range, and CV value about 7%). It has been applied to real samples of various materials involved in a controlled explosion
of an “improvised explosive device”. Three extraction procedures were tested on these samples, all employing methanol as the
solvent. The lateral flow immunoassay (LFIA), developed by using the same immunoreagents, reached a detection limit of 1 μg mL−1 when tested on the same samples analysed by CL-ELISA.
相似文献
33.
34.
The influence of the recently proposed camel's back structure of the GaP conduction band edge on the exciton spectrum is investigated theoretically. The results are in good agreement with differential absorption data and strongly support a camel's back structure, with a 4 meV central hump. The computed exciton binding energy is 18.5 meV, and when combined with recent experimental data, indicates a binding of about 32 meV for the electron-hole liquid. 相似文献
35.
We present a framework aimed to reveal directed interactions of activated brain areas using time-resolved fMRI and vector autoregressive (VAR) modeling in the context of Granger causality. After describing the underlying mathematical concepts, we present simulations helping to characterize the conditions under which VAR modeling and Granger causality can reveal directed interactions from fluctuations in BOLD-like signal time courses. We apply the proposed approach to a dynamic sensorimotor mapping paradigm. In an event-related fMRI experiment, subjects performed a visuomotor mapping task for which the mapping of two stimuli (“faces” vs “houses”) to two responses (“left” or “right”) alternated periodically between the two possible mappings. Besides expected activity in sensory and motor areas, a fronto-parietal network was found to be active during presentation of a cue indicating a change in the stimulus-response (S-R) mapping. The observed network includes the superior parietal lobule and premotor areas. These areas might be involved in setting up and maintaining stimulus-response associations. The Granger causality analysis revealed a directed influence exerted by the left lateral prefrontal cortex and premotor areas on the left posterior parietal cortex. 相似文献
36.
In vivo mapping of functional domains and axonal connectivity in cat visual cortex using magnetic resonance imaging 总被引:5,自引:0,他引:5
Kim DS Kim M Ronen I Formisano E Kim KH Ugurbil K Mori S Goebel R 《Magnetic resonance imaging》2003,21(10):1131-1140
Noninvasive cognitive neuroimaging studies based on functional magnetic resonance imaging (fMRI) are of ever-increasing importance for basic and clinical neurosciences. The explanatory power of fMRI could be greatly expanded, however, if the pattern of the neuronal circuitry underlying functional activation could be made visible in an equally noninvasive manner. In this study, blood oxygenation level-dependent (BOLD)-based fMRI and diffusion tensor imaging (DTI) were performed in the same cat visual cortex, and the foci of fMRI activation utilized as seeding points for 3D DTI fiber reconstruction algorithms, thus providing the map of the axonal circuitry underlying visual information processing. The methods developed in this study will lay the foundation for in vivo neuroanatomy and the ability for noninvasive longitudinal studies of brain development. 相似文献
37.
Elia Merzari H. Ninokata A. Mahmood M. Rohde 《Theoretical and Computational Fluid Dynamics》2009,23(5):333-351
Geometries containing a narrow gap are characterized by strong quasi-periodical flow oscillations in the narrow gap region.
The above mentioned phenomena are of inherently unstable nature and, even if no conclusive theoretical study on the subject
has been published, the evidence shown to this point suggests that the oscillations are connected to interactions between
eddy structures of turbulent flows on opposite sides of the gap. These coherent structures travel in the direction of homogeneous
turbulence, in a fashion that strongly recalls a vortex street. Analogous behaviours have been observed for arrays of arbitrarily
shaped channels, within certain range of the geometric parameters. A modelling for these phenomena is at least problematic
to achieve since they are turbulence driven. This work aims to address the use of Proper Orthogonal Decomposition (POD) to
reduce the Navier–Stokes equations to a set of ordinary differential equations and better understand the dynamics underlying
these oscillations. Both experimental and numerical data are used to carry out the POD. 相似文献
38.
Guido Barone Giuseppina Castronuouvo Vittorio Elia Maria Teresa Tosto 《Journal of solution chemistry》1986,15(2):199-210
The excess enthalpies of twelve ternary aqueous solutions of alcohols or monosaccharides containing thiourea have been determined by flow microcalorimetry at 25°C. The coefficients of the virial expansion of the excess enthalpies are compared with those reported in the literature for the same ternary solutions containing urea in place of thiourea. The cross-interaction coefficients are positive for the thiourea-alcohol systems and depend on the length and branching of the alkyl chain of the alcohols. On the other hand, they are negative for the thiourea-monosaccharide systems. Thus, thiourea, as urea, can be used as a probe to reveal differences in the behavior of families of solutes characterized by the same functional groups. The results can be interpreted in terms of the relative stabilities of hydration cospheres of hydrophobic or hydrophilic solutes toward a chaotropic agent such as thiourea.Presented at the sixth Italian meeting on Calorimetry and Thermal Analysis (AICAT) held in Naples, December 4–7, 1984. 相似文献
39.
40.
Cali F Ragalmuto A Chiavetta V Calabrese G Fichera M Vinci M Ruggeri G Schinocca P Sturnio M Romano S Romano V Elia M 《Experimental & molecular medicine》2010,42(12):842-848
Angelman syndrome (AS) is a severe neurobehavioural disorder caused by failure of expression of the maternal copy of the imprinted domain located on 15q11-q13. There are different mechanisms leading to AS: maternal microdeletion, uniparental disomy, defects in a putative imprinting centre, mutations of the E3 ubiquitin protein ligase (UBE3A) gene. However, some of suspected cases of AS are still scored negative to all the latter mutations. Recently, it has been shown that a proportion of negative cases bear large deletions overlapping one or more exons of the UBE3A gene. These deletions are difficult to detect by conventional gene-scanning methods due to the masking effect by the non-deleted allele. In this study, we have used for the first time multiplex ligation-dependent probe amplification (MLPA) and comparative multiplex dosage analysis (CMDA) to search for large deletions affecting the UBE3A gene. Using this approach, we identified a novel causative deletion involving exon 8 in an affected sibling. Based on our results, we propose the use of MLPA as a fast, accurate and inexpensive test to detect large deletions in the UBE3A gene in a small but significant percentage of AS patients. 相似文献