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981.
Map reading is unique to humans but is present in people of diverse cultures, at ages as young as 4 years old. Here, we explore the nature and sources of this ability and ask both what geometric information young children use in maps and what nonsymbolic systems are associated with their map-reading performance. Four-year-old children were given two tests of map-based navigation (placing an object within a small three-dimensional [3D] surface layout at a position indicated on a two-dimensional [2D] map), one focused on distance relations and the other on angle relations. Children also were given two nonsymbolic tasks, testing their use of geometry for navigation (a reorientation task) and for visual form analysis (a deviant-detection task). Although children successfully performed both map tasks, their performance on the two map tasks was uncorrelated, providing evidence for distinct abilities to represent distance and angle on 2D maps of 3D surface layouts. In contrast, performance on each map task was associated with performance on one of the two nonsymbolic tasks: Map-based navigation by distance correlated with sensitivity to the shape of the environment in the reorientation task, whereas map-based navigation by angle correlated with sensitivity to the shapes of 2D forms and patterns in the deviant-detection task. These findings suggest links between one uniquely human, emerging symbolic ability, geometric map use, and two core systems of geometry.  相似文献   
982.
ABSTRACT

Compared with clear-cut loss by death, ambiguous loss is defined as a loss that is not definite because the person is missing or mentally absent but physically present (e.g., through Alzheimer's disease). We expected the ambiguity of loss to show in psychologically more compromised loss memories and self-defining memories, but not in autobiographical memories in general. Thirty Chinese adults who had lost a parent through death, thirty whose parent had gone missing, and thirty who cared for a demented parent narrated their loss experiences and memories of sad and turning-point events as well as self-defining memories. Individuals with ambiguous loss narrated the loss and a self-defining memory with more contamination and fewer redemption sequences, and only the loss memory with fewer themes of agency and communion than individuals with definite loss, but not in memories of sad and turning point events. Effects of ambiguity of loss were independent of prolonged grief, which in turn independently predicted some of these effects. Thus the ambiguous quality of loss predicts effects on loss memories and self-defining memories independently of psychiatric symptoms.  相似文献   
983.
We examined whether contexts suggesting an actor's prior intentions facilitate observational learning in 2.5-year-olds. In Experiment 1, children observed an experimenter handle one box before proceeding to open a second box. In two prior intention conditions, children either watched the experimenter extract a toy from the first box or saw that the box had already been opened. In two no prior intention conditions, children watched the demonstration with only the second box or paired with irrelevant actions upon the first box. Children successfully opened the second box more often in the two prior intention conditions than in the two no prior intention conditions. Experiment 2 investigated stimulus generalization as another explanation for these results. A functionally different trap-tube task served as the pre-demonstration apparatus. Before watching the experimenter open the box, children either saw her extract a toy from the tube with a stick or observed the toy accidentally fall from the opening. In both cases, children opened the box at similar high rates. We discuss children's use of others’ prior intentions or observable outcomes in observational learning.  相似文献   
984.
ABSTRACT

The Young-Laplace equation was firstly established based on a liquid film without shearing resistance. It is not valid for a solid. By taking into account the in-plane shearing and transverse shearing within a surface layer, we reconstruct the Young-Laplace equation for a solid. This new version shows that the equilibrium of a solid surface is determined by the bulk stress, the surface membrane stress and the transverse shear stress acting together. The transverse shear stress depends on the gradient of the Gaussian curvature of the surface and the strain. The intrinsic membrane stress and transverse shear stress cause residual stresses to appear in the interior of the solid. The intrinsic transverse shear stress occurs only in a non-spherical shaped body.  相似文献   
985.
This study investigated a conceptual model with two pathways, altruism and perceived spiritual support, leading to resilience among student volunteers following Hurricanes Katrina and Rita (H‐KR). Both strengths share the sense of deep connections. Parallel pathways with the two major constructs were estimated using structural equation modeling, adjusting for demographics and peritraumatic emotional reactions. The two indicators may have served as a protective mechanism for all volunteers despite differing racial/cultural backgrounds. The potential protection of these strength factors was mediated through optimism and hope. Resilience among minority volunteers was associated more with faith‐related strengths, as indicated in the relevant pathway that also contributed to their altruistic actions. The resilience of white volunteers, however, was directly associated with altruism, a strength that does depend heavily on religious beliefs. Further, the modification index suggested a direct path from race to depression.  相似文献   
986.
987.
A thorough TEM analysis has been carried out to study the dislocations cutting into γ′ phase in a single-crystal superalloy during uniaxial tensile creep under high-temperature and low-stress conditions. It is proved that the a〈100〉 edge superdislocation originates from the interfacial a〈100〉 dislocations and moves into the γ′ phase by pure climbing. And the dissociation of the a〈100〉 superdislocation core into two a/2〈101〉 superpartial dislocations during uniaxial tensile creep has been identified by HRTEM method for the first time.  相似文献   
988.
The popularization of higher education has developed into a worldwide trend of ranking universities. In light of the lack of research from the student perspective and the non‐individualism of East Asian society, the goal of the present study was to integrate social identity theory and characteristics of Chinese achievement goals in order to determine the relationships between university rankings and students’ university identity, major identity, self‐identity, and learning satisfaction (LS). The participants included 1052 undergraduates (49.4% male, 50.6% female) from 13 universities in Taiwan. A questionnaire was conducted. The results of hierarchical regression analyses show that university ranking positively correlates with students’ university identity, major identity, and self‐identity but negatively correlates with LS due to the effect of university identity acting as a suppressor. The results of structural equation modelling show that: (1) students’ major identity and self‐identity completely mediate the effect of university identity on LS; and (2) university ranking has a significantly negative effect on LS after adding multiple identities as the suppressor and mediators. Furthermore, as students progress further into their studies, both their university identity and major identity gradually decline, while their self‐identity remains constant. Theoretical and practical implications for higher education are also discussed.  相似文献   
989.
本研究借助ERPs技术,通过操纵关键词与当前语境的语义合理性关系,考察在严格限定关键词词频变异性的情况下,语义整合过程能否反映在P2效应上。ERPs结果发现关键词呈现后,语义合理相比违背条件在右侧脑区诱发了更大的P2成分。该结果支持如果关键词低水平的变量信息(词频等)得到适当控制,ERPs技术可以检测到发生在250ms以前的语义整合过程。  相似文献   
990.
Many animals modify behavioural decisions based on information they have previously acquired. Contest behaviour is often affected by previous contest experiences: individuals behave more and less aggressively after a victory and defeat, respectively (winner/loser effect). Individuals in the field sometimes encounter multiple competitors in quick succession, but whether these experiences interact to influence each other’s importance is unclear. We tested five hypotheses for experience interaction (no interaction, retroactive interference, proactive interaction, reinforcement and diminishing returns) using Kryptolebias marmoratus. Focal individuals were paired up with opponents having the same 1-month contest outcome (1 month before the experiment), as this difference in actual or perceived fighting ability has been shown to affect the fish’s response to new experiences. We gave the focal individual of a pair a winning or losing experience on day 1. Then both fish of the pair received the same winning, losing or no-contest experience on day 2. Then we organised fights between the two. The effect of a day-1 losing experience did depend on the fish’s actual or perceived fighting ability: one-month losers readily showed loser effects from the day-1 losing experience, irrespective of the day-2 experience (i.e. no interaction between day-1 and day-2 experiences). One-month winners, however, only showed loser effects from a day-1 losing experience when the day-2 experience was also a loss (i.e. reinforcement). Day-1 winning experiences did not interact with day-2 experiences in 1-month losers or winners. Therefore, multiple experiences sometimes reinforce each other, but how they combine to influence behaviour depends on an individual’s actual or perceived fighting ability.  相似文献   
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