Overgeneral autobiographical memory in children of depressed mothers

The goal of this study was to examine overgeneral autobiographical memory in a population at-risk for depression (i.e., children of depressed mothers). We predicted that children of depressed mothers would display less-specific memories than children of non-depressed mothers and that these results would be observed among children with no prior history of depression themselves. Participants in this study were children (age 8–14; 50% girls, 83% Caucasian) of mothers with (n = 103) or without (n = 120) a history of major depressive disorder during the child's life. Mothers' and children's diagnoses were confirmed with a diagnostic interview, and children completed the Autobiographical Memory Test and a measure of depressive symptoms. We found that children of depressed mothers, compared to children of non-depressed mothers, recalled less-specific memories in response to negative cue words but not positive cue words. Importantly, these results were maintained even when we statistically controlled for the influence of children's current depressive symptom levels and excluded children with currently depressed mothers. These results suggest that overgeneral autobiographical memory for negative events may serve as a marker of depression risk among high-risk children with no prior depression history.     

Whom do children copy? Model-based biases in social learning

This review investigates the presence of young children’s model-based cultural transmission biases in social learning, arguing that such biases are adaptive and flexible. Section 1 offers five propositions regarding the presence and direction of model-based transmission biases in young children’s copying of a model. Section 2 discusses the cognitive abilities required for differing model-based biases and tracks their development in early childhood. Section 3 suggests future areas of research including considering the social aspect of model-based biases and understanding their use within a comparative perspective.     

环境雌激素双酚A对成年小鼠学习记忆和突触结构的影响*

双酚A (bisphenol, BPA)是一种广泛存在的环境内分泌干扰物,它可与雌激素受体结合干扰内源性雌激素对中枢神经系统的调控作用。本研究通过将10周龄小鼠灌胃染毒BPA (0.4、4、40 mg/kg/day)3个月,研究长期BPA暴露对成年小鼠记忆行为和突触可塑性的影响。开场行为测试结果表明, BPA (0.4、4、40 mg/kg/day)增加雄性的站立次数和理毛频率, BPA (4 mg/kg/day)却显著减少雌鼠的站立次数。水迷宫和被动回避行为模型检测显示, BPA主要损伤雄鼠的空间学习记忆和被动回避记忆。通过制备海马CA1区超薄切片后,电镜观测发现, BPA (0.4、40 mg/kg/day)暴露降低雄鼠海马CA1区突触数密度,缩短雄鼠突触前活性带长度,减小雄鼠突触后致密体(PSD)厚度,增加雄鼠突触间隙宽度。进一步用Western blot方法检测突触前、后的标志性蛋白Synapsin I和PSD95以及兴奋性氨基酸NMDA受体NR1亚基和AMPA受体GluR1亚基蛋白的表达,发现BPA暴露致雄鼠Synapsin I、PSD95、NR1蛋白表达水平下调。而BPA对雌鼠的记忆行为、突触形态、突触蛋白和受体蛋白均没有明显作用。以上结果提示长期B PA暴露性别特异性地影响成年小鼠的活动性和探究行为,损伤雄鼠的学习记忆,这些作用可能通过下调突触蛋白和NMDA受体的表达而负性影响突触结构可塑性,最终影响雄鼠的学习记忆功能。     

Formation of Ga–Pd–Sc icosahedral quasicrystal and approximant phases

ABSTRACT

We report the formation of an icosahedral quasicrystal and its approximant in the Ga–Pd–Sc alloy. The primitive-type quasicrystal with a six-dimensional lattice constant of 0.713?nm formed in the melt-quenched Ga₅₃Pd₃₀Sc₁₇ alloy, with a similar composition to that of the Ga₅₅Pd₃₀Sc₁₅ 1/1 approximant. The atomic-scale observation and chemical analysis of the 1/1 approximant by scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy showed that the approximant consisted of Tsai-type clusters with a characteristic chemical ordering. Furthermore, a series of approximants were observed in the Ga₅₅Pd₃₀RE₁₅ alloys by replacing Sc with other rare-earth elements (REs) (RE?= Y, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu). These approximants, which have relatively small lattice constants and consequently smaller RE–RE distances compared with those for other RE-containing Tsai-type approximants, may be candidates for materials with novel electronic and magnetic properties similar to those observed in Au-based quasicrystals and approximants.     

Formation of FeNi with L10-ordered structure using high-pressure torsion

FeNi with the L1₀-ordered structure is formed over an astronomical timescale in meteorites. In this study, severe plastic deformation using high-pressure torsion (HPT) is employed for the production of the L1₀ structure in the laboratory. Its formation is confirmed by X-ray diffraction analysis and transmission electron microscopy. Processing of elemental nanopowders by HPT is an effective method for the formation of the L1₀ phase, which is enhanced by the addition of Co to FeNi or annealing after HPT. The formation of the phase must be associated with enhanced diffusion through HPT.     

Secondary defects induced by ion and electron irradiation of GaSb

Secondary defects induced by ion and electron irradiation up to 6?dpa (displacements per atom) at liquid-nitrogen temperature in GaSb thin films are compared. For Sn ion (60?keV) irradiation, voids were observed. However, for high-energy electron (2?MeV) irradiation, interstitial-type dislocation loops were produced. The densities of voids and interstitial-type dislocation loops were almost equivalent (8?×?10¹⁴?voids/m² and 3?×?10¹⁴?loops/m²) after irradiations at the same damage level of 6?dpa. It is concluded that the formation of voids by ion irradiation follows the creation of localised vacancy defects in cascade damage.     

Effect of cooling rate on size-dependent atomic ordering of CoPt nanoparticles

We report on the effect of cooling rate on the size-dependent atomic ordering of CoPt nanoparticles using aberration corrected high-resolution transmission electron microscopy. It was found that cooling rate plays a crucial role in promoting atomic ordering during the cooling process after annealing. Nanoparticles of ≈3?nm in diameter show the A1-disordered phase after annealing at 873?K for 1?h followed by rapid cooling (110?K/min), while the L1₀-ordered phase is obtained when the cooling rate is slow (1.5?K/min). The disordered phase is also obtained by rapid cooling after annealing at 973?K for 1?h. These results unambiguously indicate that the order–disorder transformation temperature is reduced to a temperature at least lower than 873?K for CoPt nanoparticles smaller than 3?nm in diameter. The slow cooling process promotes the atomic ordering, which resulted in an enhancement of magnetic coercivity as high as 2200?Oe. This study demonstrates that hard magnetic properties of the CoPt nanoparticles can be improved by controlling the cooling rate after heat treatments.     

Healers,Leaders and Entrepreneurs: Shamanic Revival in Southern Siberia

While it is generally agreed that in the postmodern world all tradition is invented, in many post-colonial contexts the emerging identities are spelled out in the idiom of ‘traditional heritage’. This article considers the social field of ‘shamanism’ as it has been shaped in the post-Soviet years in Tuva, an autonomous republic within the Russian Federation in Southern Siberia, and analyses Tuvan shamanism as a product of local historical and social forces, and global processes. Based on both the ethnography of the organisational structure of contemporary Tuvan shamanism, and portraits of different categories of practitioners, the article analyses continuity and change in various aspects of what is locally seen as ‘traditional knowledge’, and discusses different skills, orientations, and divisions of labour among the practitioners. Shamanism in post-Soviet Siberia is seen as a postmodern religious movement enmeshed in global structures and processes, and it is only in this context that a local tradition can become alive and meaningful again.     

A Review of Reviews Examining Neurological Processes Relevant to Impact of Parental PTSD on Military Children: Implications for Supporting Resilience

In this study, 10 recent meta-analytic and systematic review studies were synthesized on the neurological underpinnings of stress and trauma with implications for the impact of parental post-traumatic stress disorder (PTSD) and resilience among military children. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) group guidelines and utilizing a validated quality assessment tool, this systematic review of reviews incorporated results from more than 35,971 individuals with stress exposures, effects, or disorders and healthy controls. This synthesis found support for important gene, physiology, and environment correlations and interactions that predict increased risk for stressful life events and PTSD, but not direct transmission, among military children. Future research is needed to determine if these constitute indirect pathways of intergenerational transmission in military children.