Bitter struggle for survival: Evolved bitterness embodiment of survival motivation

In four experiments, we tested the hypothesis that survival motivation is grounded in the physical experience of bitter taste. Chinese (Experiment 1) and non-Chinese participants (Experiment 2) who tasted a bitter drink were quicker than the control participants who drank plain water in responding to survival-related words in a lexical decision task. Chinese participants who chewed bitter lotus root were more likely to discount the future than those who chewed sour lemon (Experiment 3). Finally, surprise retention tests revealed that experiencing a bitter rather than sweet taste led to higher retention of words processed for survival rather than mating scenarios (Experiment 4). These findings support our prediction that the taste of bitterness embodies survival motivation because both are adaptations to harsh environment.     

CXCL12/CXCR4轴介导的信号通路与急性白血病

趋化因子受体CXCR4与其特异性配体CXCL12结合,形成CXCL12/CXCR4生物学轴,可以介导体内多个信号通路的转导,并受多种因子的调节,与白血病细胞的存活、生长、迁移、浸润、耐药、复发等密切相关.针对CXCL12/CXCR4轴的靶向治疗为白血病的治疗开辟了新途径.     

腔镜甲状腺手术入路研究进展

内镜应用于临床已经二十余年,内镜新技术的发展和应用,使外科领域发生了翻天覆地的变化,微创腔镜辅助和完全腔镜下甲状腺手术迅速发展,许多外科医师已经成功开展了腔镜下甲状腺癌根治术,并尝试应用达芬奇机器人手术治疗甲状腺癌,取得了很好的效果,但达芬奇手术和腔镜手术的孰优孰劣还需要大样本和随机对照研究,临床上仍有许多亟待解决的问题.     

负性情绪对压抑遗忘记忆的影响

该实验使用Think/No-think(T/NT)任务,从外显和内隐记忆两个方面探讨负性情绪、测试时间对压抑遗忘的影响。实验结果表明:在外显记忆成绩中情绪与T/NT任务的交互作用显著,在NT条件下中性词回忆的成绩优于负性词,同时,情绪的主效应显著,被试对中性词的记忆显著高于负性词。但是T/NT任务的主效应不显著,情绪×T/NT任务×测试时间的交互不显著。在内隐记忆成绩中,在所有条件下的记忆成绩均无显著性差异。     

跨期选择的认知机制与神经基础

跨期选择是指个体对发生在不同时间的成本与收益进行权衡的决策过程。跨期选择的计算模型从经济学的角度用数学模型来建构时间折扣函数,而认知成分模型则从心理学的角度来研究跨期选择中的心理效应与认知成分。跨期选择的神经基础有三种不同的研究取向：双机制加工取向、单机制加工取向、自我控制取向。未来研究应该在跨期选择的认知机制、神经通路及运行机制、跨期选择的应用,以及从进化的角度对人与动物的跨期选择行为进行更深入的研究。     

父母教养方式对羞怯的作用机制

以752名大学生为被试,考察了父母教养方式与羞怯的关系以及社会支持在其中的中介作用和应对方式在其中的调节作用。结果发现：（1）母亲惩罚严厉和父亲过度保护对羞怯有显著的正向作用,父亲情感温暖对羞怯有显著的负向作用;（2）在母亲惩罚严厉和父亲情感温暖对羞怯的作用中,社会支持起着中介作用;（3）父亲过度保护对羞怯的正向作用受到幻想的调节。     

A new orthorhombic approximant of the icosahedral Al–Cu–Fe quasicrystal

We report on the formation of a new crystalline approximant phase of the icosahedral (i-)Al–Cu–Fe quasicrystal. This phase is formed during sintering of Al-based composites reinforced with i-AlCuFeB quasicrystalline particles. The structure of this phase has been characterized by transmission electron microscopy (TEM) and high-resolution electron microscopy (HREM). TEM revealed that it is a B-centred orthorhombic phase with lattice parameters a = 1.166 nm, b = 1.195 nm and c = 3.44 nm. Its chemical composition, as determined by electron energy loss spectroscopy (EELS), is close to Al_76.9Cu_2.7Fe_20.4, with an average number of valence electrons per atom e/a of 1.92, similar to the value in all other approximants of the i-phase discovered thus far. Initial results on local atomic arrangements along one of its pseudo-5-fold axes are also presented.     

Deformation mechanism of long-period TiAl 2

The microstructure of long-period TiAl 2 deformed at room temperature has been studied by means of transmission electron microscopy. Dislocations, stacking faults and twins were found to contribute to the deformation. A screw superdislocation with Burgers vector d 110] dissociates into two ½ d 110] super-partial dislocations associated with an antiphase boundary. The ½; d 110] super-partial dislocation further dissociates into two Shockley partial dislocations associated with a portion of complex intrinsic stacking fault on the closest-packed {111} plane. The propagation of stacking faults on successive {111} planes yields an order twin.     

Surface effect on the screw dislocation mobility over the Peierls barrier

The effect of the image force on the Peierls stress (τ _p ) of a screw dislocation below a free surface is studied via a self-consistent semidiscrete variational Peierls–Nabarro model. The consequence of reduction in elastic energy and increase in stacking fault energy by the presence of the free surface is found to additively increase the Peierls stress (τ _p ). This model gives a physical interpretation of the same tend observed in a recent molecular dynamic study, while previous continuum analysis predicted the opposite.     

Investigation of {111} stacking faults and nanotwins in epitaxial BaTiO3 thin films by high-resolution transmission electron microscopy

{111} stacking faults and nanotwins in epitaxial BaTiO₃ thin films on MgO substrates have been investigated by high-resolution transmission electron microscopy. In many cases, the stacking faults and nanotwins were found to be accompanied by partial dislocations. These partial dislocations can be classified as two different types, analogous to the situation in the fcc structure. One is of the Shockley type with the Burgers vector (a/3)<112>. The other is of the Frank type with the Burgers vector (a/3)<111>. The movements of both types of partial can lead to the {111} stacking faults and the {111} twins observed in these films.