Hemispheric contributions to the integration of visual and auditory information in speech perception

Differential hemispheric contributions to the perceptual phenomenon known as the McGurk effect were examined in normal subjects, 1 callosotomy patient, and 4 patients with intractable epilepsy. Twenty-five right-handed subjects were more likely to demonstrate an influence of a mouthed word on identification of a dubbed acoustic word when the speaker's face was lateralized to the LVF as compared with the RVF. In contrast, display of printed response alternatives in the RVF elicited a greater percentage of McGurk responses than display in the LVF. Visual field differences were absent in a group of 15 left-handed subjects. These results suggest that in right-handers, the two hemispheres may make distinct contributions to the McGurk effect. The callosotomy patient demonstrated reliable McGurk effects, but at a lower rate than the normal subjects and the epileptic control subjects. These data support the view that both the right and left hemisphere can make significant contributions to the McGurk effect.     

Densification of silicon nitride ceramics under sinter-HIP conditions

The influence of several sinter-HIP variables on the densification behaviour of silicon nitride-based ceramics has been investigated. The processing conditions were studied for Si₃N₄ powder mixtures containing controlled amounts of Y₂O₃+Al₂O₃ or Y₂O₃+MgO. The specimens were subjected to sinter-HIP cycles under argon or nitrogen atmospheres at various temperatures and pressures. The final density of the powder compacts exhibited a strong dependence not only on the applied pressure, the composition and the processing temperature, but also on the pressurization rate and the initial pressurization time. The microstructural changes induced by the application of high pressure were followed by transmission electron microscopy. On examination by TEM, large concentrations of dislocations, generated inside some-Si₃N₄ grains, were observed. Characterization of these dislocations showed thatb=0001 is their most frequently found Burgers vector. Also, two relaxation mechanisms, tending to release the stored energy of deformation in the-Si₃N₄ grains, namely grain penetration (a form of strain-induced boundary migration) and grain fragmentation (the formation of subgrains due to rearrangement of dislocations into low energy configurations), have been identified. The intergranular phases formed were characterized by energy dispersive X-ray spectroscopic analysis, X-ray diffraction and electron diffraction. The influence of different sinter-HIP cycles on the transformation of silicon nitride without additives was also investigated by X-ray diffractometry.     

Thermal conductivity of liquid n-alkanes

The thermal conductivity of liquids has been shown in the past to be difficult to predict with a reasonable accuracy, due to the lack of accurate experimental data and reliable prediction schemes. However, data of a high accuracy, and covering wide density ranges, obtained recently in laboratories in Boulder, Lisbon, and London with the transient hot-wire technique, can be used to revise an existing correlation scheme and to develop a new universal predictive technique for the thermal conductivity of liquid normal alkanes. The proposed correlation scheme is constructed on a theoretically based treatment of the van der Waals model of a liquid, which permits the prediction of the density dependence and the thermal conductivity of liquid n-alkanes, methane to tridecane, for temperatures between 110 and 370 K and pressures up to 0.6 MPa, i.e., for 0.3T/T _c0.7 and 2.4P/P _c3.7, with an accuracy of ±1%, given a known value of the thermal conductivity of the fluid at the desired temperature. A generalization of the hard-core volumes obtained, as a function of the number of carbon atoms, showed that it was possible to predict the thermal conductivity of pentane to tetradecane±2%, without the necessity of available experimental measurements.     

High-speed techniques for estimating t1, t2, and density images

This work presents methods for estimating relaxation times T1 and T2 and proton density using a real time digital video processor. This device performs each mathematical step of the fitting algorithms in one video frame interval (1/30 s). Two-point fits of T1 and T2 may be generated in approximately 15 video frame intervals or about 0.5 s; generation of a T2 image from four acquired images requires about 30 video frame intervals or about 1 s. The hardware is common to many commercial MR scanners and requires no array processor. Such high-speed techniques can expedite the clinical use of computed images and facilitate the implementation of image synthesis.     

A genetic tango attack against the David–Prasad RFID ultra‐lightweight authentication protocol

Radio frequency identification (RFID) is a powerful technology that enables wireless information storage and control in an economical way. These properties have generated a wide range of applications in different areas. Due to economic and technological constrains, RFID devices are seriously limited, having small or even tiny computational capabilities. This issue is particularly challenging from the security point of view. Security protocols in RFID environments have to deal with strong computational limitations, and classical protocols cannot be used in this context. There have been several attempts to overcome these limitations in the form of new lightweight security protocols designed to be used in very constrained (sometimes called ultra‐lightweight) RFID environments. One of these proposals is the David–Prasad ultra‐lightweight authentication protocol. This protocol was successfully attacked using a cryptanalysis technique named Tango attack. The capacity of the attack depends on a set of boolean approximations. In this paper, we present an enhanced version of the Tango attack, named Genetic Tango attack, that uses Genetic Programming to design those approximations, easing the generation of automatic cryptanalysis and improving its power compared to a manually designed attack. Experimental results are given to illustrate the effectiveness of this new attack.     

On Yager and Hamacher t‐Norms and Fuzzy Metric Spaces

Recently, Gregori et al. have discussed (Fuzzy Sets Syst 2011;161:2193–2205) the so‐called strong fuzzy metrics when looking for a class of completable fuzzy metric spaces in the sense of George and Veeramani and state the question of finding a nonstrong fuzzy metric space for a continuous t‐norm different from the minimum. Later on, Gutiérrez García and Romaguera solved this question (Fuzzy Sets Syst 2011;162:91–93) by means of two examples for the product and the Lukasiewicz t‐norm, respectively. In this direction, they posed to find further examples of nonstrong fuzzy metrics for continuous t‐norms that are greater than the product but different from minimum. In this paper, we found an example of this kind. On the other hand, Tirado established (Fixed Point Theory 2012;13:273–283) a fixed‐point theorem in fuzzy metric spaces, which was successfully used to prove the existence and uniqueness of solution for the recurrence equation associated with the probabilistic divide and conquer algorithms. Here, we generalize this result by using a class of continuous t‐norms known as ω‐Yager t‐norms.     

A Class of Incomplete Riemann Solvers Based on Uniform Rational Approximations to the Absolute Value Function

In this paper we propose a new class of incomplete Riemann solvers, based on approximations in the \(L^\infty \) -norm to the absolute value function in \([-1,1]\) by means of rational functions, for the numerical approximation of the solution of hyperbolic systems of conservation laws. The main idea relies on the construction of a numerical approximation to the viscosity matrix by using an appropriate rational real function \(R(x)\) , that approximates the function \(|x|\) uniformly in \([-1,1]\) , evaluated at the Jacobian of the fluxes of the hyperbolic system computed at some average value (for example, Roe averages). In addition to the Jacobians of the fluxes we shall use either the maximum in absolute value of the characteristic speeds in each cell or an upper bound of them. Thus, the resulting approximate Riemann solver is incomplete in the sense that we do not use the complete spectral decomposition of the Jacobian. Moreover, the new class of Riemann solvers consists of a hierarchy of schemes running from the more dissipative to the less dissipative ones, and having as limiting case a Roe-like scheme. According to the order of the approximation of the generating rational function used, the degree of dissipation can be dosed for particular applications. We study different rational approximations: Newman-type functions, iterative generated Halley functions, and also Chebyshev polynomial approximants. We test our basic algorithms for different initial value Riemann problems for ideal gas dynamics (HD) and magnetohydrodynamics (MHD) to observe their behavior with respect to challenging scenarios in numerical simulations, including some standard numerical pathologies (e. g., heat conduction, postshock oscillations and overheating) and the formation of compound waves in ideal MHD. We also examine our proposed schemes, by computing the numerical approximation of different initial value problems for nonconservative multilayer shallow water equations, where it has been observed that intermediate waves can be properly captured for an appropriate degree of approximation of the generating rational function used. Our numerical tests indicate that the proposed schemes are robust, running stable and accurate with a satisfactory time step restriction (CFL constant), and the computational cost is more advantageous with respect to schemes that use a complete spectral decomposition of the Jacobians.     

Phosphate availability in calcareous Vertisols and Inceptisols in relation to fertilizer type and soil properties

The availability to plants of fertilizer phosphorus (P) applied to soil, as measured by chemical extraction, is used to estimate P fertilizer needs. We studied the availability of P, applied as monocalcium phosphate (MCP) powder, ordinary superphosphate (OSP) granules and diammonium phosphate (DAP) granules in 24 calcareous Vertisols and Inceptisols of Andalusia, Spain, by using laboratory incubation techniques. The soils differed widely in their P adsorption- and Ca-phosphate precipitation-related properties. For MCP, availability (defined as the proportion of added P that is recovered by extraction with NaHCO₃ or is isotopically exchangeable) decreased markedly with incubation time and increasing addition rate. The mean recoveries after 180 d of incubation at field capacity at a rate of 246 mg P kg^–1 soil were 17% for Olsen P, 38% for Colwell P, and 16% for isotopically exchangeable P (IEP). Increasing the application rate to 2460 mg kg^–1 resulted in recoveries of 6% for Olsen P, 25% for Colwell P, and 4% for IEP. While IEP-based recovery was not significantly correlated to any soil property, that based on Olsen P (and, to a lesser extent, Colwell P) decreased sharply with increase in the ratio of clay (or Fe oxides) to total (or active) calcium carbonate equivalent. Accordingly, Olsen P might overestimate P availability in those soils relatively rich in carbonate and poor in clay and Fe oxides. On the other hand, recovery of applied P from soils containing more clay and Fe oxides, by a sequential extraction (with H₂O, two 0.5M NaHCO₃ treatments, 0.5M HCl), was lower than 100%, thereby suggesting phosphate occlusion by Fe oxides or clay.Availability of the fertilizers tested 90 d after application was found to decrease in the following order: MCP powder (rate, 246 mg kg^–1) > DAP granules (rate, 547 mg kg^–1) > MCP powder (rate, 738 mg kg^–1) > OSP granules (rate, 308 mg kg^–1). Differences between fertilizers tended to increase with increasing carbonate content in the soil. This may have been due to precipitation of Ca phosphates caused by the presence of Ca in the fertilizer and the high Ca- supplying capacity of the more calcareous soils.     

Comparative study of the physical aging of the epoxy systems BADGE n = 0/m‐XDA and BADGE n = 0/m‐XDA/PEI

The physical aging of the epoxy network consisting of a diglycidyl ether of bisphenol A, m‐xylylenediamine, and polyetherimide was studied by differential scanning calorimetry. The glass transition temperature and the variation of the specific heat capacities have been calculated using the method, based on the intersection of both enthalpy–temperature lines for glassy and liquid states. The apparent activation energy (E_H) was calculated using a single method that involved separate temperature and excess enthalpy dependency. All calorimetric data were compared with those obtained for the epoxy network without thermoplastic. thermoplastic. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3931–3935, 2006     

Li influx and binding, and li/mg competition in bovine chromaffin cell suspensions as studied by li NMR and fluorescence spectroscopy

Li(+) influx by bovine chromaffin cells, obtained from bovine adrenal medulla, was studied in intact cell suspensions using (7)Li NMR spectroscopy with the shift reagent [Tm(HDOTP)](4-). The influx rate constants, k(i), were determined in the absence and in the presence of two Na(+) membrane transport inhibitors. The values obtained indicate that both voltage sensitive Na(+) channels and (Na(+)/K(+))-ATPase play an important role in Li(+) uptake by these cells. (7)Li NMR T(1) and T(2) relaxation times for intracellular Li(+) in bovine chromaffin cells provided a T(1)/T(2) ratio of 305, showing that Li(+) is highly, immobilized due to strong binding to intracellular structures. Using fluorescence spectroscopy and the Mg(2+) fluorescent probe, furaptra, the free intracellular Mg(2+) concentration in the bovine chromaffin cells incubated with 15 mM LiCl was found to increase by about mM after the intracellular Li(+) concentration reached a steady state. Therefore, once inside the cell, Li(+) is able to displace Mg(2+) from its binding sites.