数学认知能力的遗传证据研究综述

数学认知能力是人类最重要的高级认知功能之一,许多研究者对其遗传性给出了相关的证据。本文从数感具有跨种系的特点、婴儿具有数量辨别能力、数学遗传的双生子研究以及遗传综合症病人的研究等间接和直接证据层面对数学认知能力的遗传性研究进行了简要的总结分析,指出对数学认知能力的遗传基因研究还需要从正常人的角度做进一步的研究探索,以便真正找到数学能力的遗传基因。     

语境、意向与意义——兼评塞尔的意向性意义理论

塞尔在其前期理论把语言的意义归之于言语行为,特别是交流意向,但在其后期理论则把意义归结为表征意向,而交流意向派生于表征意向,甚至割断了意义和交流之间的联系。笔者通过引入语境因素和指称意向的概念,澄清了语境、意向和意义之间的关系,使塞尔具有私人性的表征意向和交流意向具有一定的公共性,以此扭转塞尔理论中的心理主义趋向,回归到弗雷格的反心理主义的语义学进路。     

Beauty is better pursued: effects of attractiveness in multiple-face tracking

Using the multiple-object tracking paradigm, this study examines how spontaneous appraisal for facial beauty affects distributed attention to multiple faces in dynamic displays. Observers tracked attractive faces more effectively than unattractive faces in this task. Tracking performance was only affected by target attractiveness, suggesting an absence of appraisal for distractor attractiveness. Attractive male faces also produced stronger binding of face identity and location for female participants. Together, the results suggest that facial attractiveness was appraised during tracking even though this was task irrelevant. Contrary to the theory that multiple-object tracking is driven by encapsulated low-level vision, our results show that the content of target representation is not only penetrable by social cognition but also modulates the course of tracking operations.     

Life values and mental health: A longitudinal study comparing chronically ill women to women without chronic disease

We tested the hypothesis that among women who are chronically ill, a re-ordering of life values maintains mental health. A community-based prospective longitudinal study was conducted in which data were obtained from 601 women in 1986, when the women were with mean age 42 and again in 2003, when the women were with mean age 58. There was a significant change in life values as women aged with more change among women with chronic disease (n = 476) than those without chronic disease (n = 125). Increased valuation of intrinsic life values (health and love) and decreased valuation of extrinsic life values (power, fame and attractiveness) were associated with subsequent better mental health for women with chronic disease, but not for those without chronic disease.     

Pinning of grain boundary migration by a coherent particle

We studied single-particle pinning of grain boundary (GB) migration during grain growth. A phase-field model was formulated to simulate the pinning by a coherent particle and validated quantitatively by comparison with analytical prediction. A study of GB migration velocity using this model revealed that second-phase coherent particles have a previously unknown restraining effect over the whole of the GB-particle interaction range, which is qualitatively different from the interaction between GB and incoherent particles.     

Revealing texture architecture in a surface gradient nanostructured Al-Cu-Mg alloy

ABSTRACT

A multiscale crystallographic texture architecture in a surface gradient nanostructured Al-Cu-Mg alloy after surface sliding friction treatment (SSFT) has been revealed by a combination of electron backscatter diffraction and precession electron diffraction (PED)-assisted transmission electron microscopy (TEM) orientation mapping. Accompanying a grain structure variation from lamellar coarse grains to equiaxed nanograins, the major texture components evolve from brass {110}<112> in the coarse-grain matrix, Goss {110}<001> at a depth of ～80?μm, E {111}<011> and F {111}<112> at a depth of ～20?μm, to a mixture of rotated cube {001}<110>, E and F in the topmost surface layer. The through-thickness textural development and evolution are attributed to the cyclic loading of concurrent shear and compression during the SSFT processing. The PED-assisted orientation mapping shows good capability in mapping severe plastic-deformation-induced nanostructures with large residual strains and high defect density.     

Approximant phases,phason planes and domain-boundary networks in Al−Ni−Rh alloys

Structurally complicated ξ′- and ξ-phases have been found, for the first time, in as-cast Al₇₃Ni₅Rh₂₂ and Al₇₅Ni₁₅Rh₁₀ alloys. The lattice parameters of these two phases were determined by means of electron diffraction and high-resolution transmission electron microscopy (HREM). These two phases have similar orthorhombic structures but with different lattice parameters of a?=?23.2?Å, b?=?16.4?Å, c?=?12.0?Å for the ξ′-phase and a?=?20.3?Å, b?=?16.4?Å, c?=?14.8?Å for the ξ-phase. A new two-dimensional domain-boundary network has also been observed in these two phases. Domain boundaries with normals closely parallel to the [001] direction are actually phason planes represented by a translation vector of r?=(1/2)a?+(1/2τ)c in the ξ′-phase and r=±(1/2τ²) a?+(τ/2)c in the ξ-phase, whereas the newly-found wide and zigzag boundaries perpendicular to the above set were attributed from the step-like boundary structures of domains related by a translation vector of r?=(1/τ)((1/2)a?+(1/2τ)c). The structural difference between the two types of planar faults is discussed.     

Effects of temperature and electron energy on the electron-irradiation-induced decomposition of sapphire

The effects of temperature and electron energy on the electron-irradiation-induced decomposition of sapphire have been investigated by in situ transmission electron microscopy (TEM). It was found that the decomposition rate of α-Al₂O₃ increased with increasing irradiation temperature and decreased with increasing acceleration voltage. The core-hole Auger decay process (K–F model), rather than knock-on displacement, is responsible for the decomposition of α-Al₂O₃ under electron irradiation.     

Transformation-induced elastic strain effect on the precipitation kinetics of ordered intermetallics

Abstract

A transformation-induced elastic strain effect on the decomposition kinetics of a disordered phase into a mixture of ordered and disordered phases was investigated for a prototype binary alloy in two dimensions (2-D) by using a computer simulation technique. The simulation technique not only described simultaneously different processes, such as atomic ordering, clustering, disordering and coarsening, but also produced automatically ordered structures and alloy morphologies. It was found that irrespective of the degree of the crystal lattice mismatch between precipitates and the matrix, the alloy morphologies, developed during the congruent ordering stage which preceded the decomposition, showed no alignment in any of the crystallographic directions. Alignment developed during subbequent decomposition of the congruently ordered single phase, which resulted in the appearance of an equilibrium disordered phase preferentially along the antiphase domain boundaries. It became increasingly pronounced as the time of alloy aging increased. The aligned morphology finally formed the modulated structure found in many alloys. This mechanism of modulated structure formation is new since almost all previous experimentally observed modulated structures were interpreted as a result of a homogeneous spinodal decomposition. The predicted kinetics was found to be in excellent agreement with recent experimental results in a Fe-Si system and should be expected in most two-phase alloys with an ordered intermetallic precipitate whose stress-free lattice constant is significantly different from that of the disordered matrix.     

Elastic solutions with arbitrary elastic inhomogeneity and anisotropy

An efficient numerical algorithm is proposed to accurately compute the elastic fields in two-dimensional (2D) or three-dimensional (3D) microstructures with arbitrary elastic inhomogeneity and anisotropy. It combines the equivalent inclusion method of Eshelby, the microelasticity theory of Khachaturyan, and the spectral iterative perturbation method of Hu and Chen. Its efficiency is compared with those of existing approaches in the literature. The method can be conveniently implemented in phase-field modeling of stress-dependent microstructure evolution and/or of mass/electrical transport.