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231.
The sequential patterning of complex acoustic elements is a salient feature of bird song and other forms of vocal communication. For European starlings (Sturnus vulgaris), a songbird species, individual vocal recognition is improved when the temporal organization of song components (called motifs) follows the normal patterns of each singer. This sensitivity to natural motif sequences may underlie observations that starlings can also learn more complex, unnatural motif patterns. Alternatively, it has been proposed that the apparent acquisition of abstract motif patterning rules instead reflects idiosyncrasies of the training conditions used in prior experiments. That is, that motif patterns are learned not by recognizing differences in temporal structures between patterns, but by identifying serendipitous features (e.g., acoustical cues) in the small sets of training and testing stimuli used. Here, we investigate this possibility, by asking whether starlings can learn to discriminate between two arbitrary motif patterns, when unique examples of each pattern are presented on every trial. Our results demonstrate that abstract motif patterning rules can be acquired from trial-unique stimuli and suggest that such training leads to better pattern generalization compared with training with much smaller stimulus subsets.  相似文献   
232.
This study investigated the relationship between social support and symptoms of posttraumatic stress among adolescents who were exposed to the 2008 Wenchuan earthquake in China. The results showed that three sources of social support—support from family, support from friends, and support from significant others—have significant main effects on posttraumatic stress disorder (PTSD). Buffering effects of social support were not supported. Gender and residency were also associated with PTSD, with female adolescents and adolescents from rural areas demonstrating higher levels of PTSD than their male counterparts and adolescents from urban and township areas.  相似文献   
233.
The nucleation undercoolings of non-magnetic metals like paramagnetic aluminium in high magnetic fields were measured by the differential thermal analysis technique. It was shown that the nucleation undercooling of pure aluminium increased with increasing the magnetic field, while its melting temperature was hardly changed. Based on the model of magnetic dipoles at the interface, it is proposed that the magnetic-field-induced interfacial energy mainly contributes to the increase in undercooling. The change in undercooling in the magnetic field is calculated theoretically, which is in comparison with experimental data. Additionally, the inhibition of atom diffusion in the magnetic field plays a role in the change of undercooling.  相似文献   
234.
The purpose of this research is to quantitatively compare everyday situational experience around the world. Local collaborators recruited 5,447 members of college communities in 20 countries, who provided data via a Web site in 14 languages. Using the 89 items of the Riverside Situational Q‐sort (RSQ), participants described the situation they experienced the previous evening at 7:00 p.m. Correlations among the average situational profiles of each country ranged from r = .73 to r = .95; the typical situation was described as largely pleasant. Most similar were the United States/Canada; least similar were South Korea/Denmark. Japan had the most homogenous situational experience; South Korea, the least. The 15 RSQ items varying the most across countries described relatively negative aspects of situational experience; the 15 least varying items were more positive. Further analyses correlated RSQ items with national scores on six value dimensions, the Big Five traits, economic output, and population. Individualism, Neuroticism, Openness, and Gross Domestic Product yielded more significant correlations than expected by chance. Psychological research traditionally has paid more attention to the assessment of persons than of situations, a discrepancy that extends to cross‐cultural psychology. The present study demonstrates how cultures vary in situational experience in psychologically meaningful ways.  相似文献   
235.
The conventional setup for multi-group structural equation modeling requires a stringent condition of cross-group equality of intercepts before mean comparison with latent variables can be conducted. This article proposes a new setup that allows mean comparison without the need to estimate any mean structural model. By projecting the observed sample means onto the space of the common scores and the space orthogonal to that of the common scores, the new setup allows identifying and estimating the means of the common and specific factors, although, without replicate measures, variances of specific factors cannot be distinguished from those of measurement errors. Under the new setup, testing cross-group mean differences of the common scores is done independently from that of the specific factors. Such independent testing eliminates the requirement for cross-group equality of intercepts by the conventional setup in order to test cross-group equality of means of latent variables using chi-square-difference statistics. The most appealing piece of the new setup is a validity index for mean differences, defined as the percentage of the sum of the squared observed mean differences that is due to that of the mean differences of the common scores. By analyzing real data with two groups, the new setup is shown to offer more information than what is obtained under the conventional setup.  相似文献   
236.
Moderation analysis has many applications in social sciences. Most widely used estimation methods for moderation analysis assume that errors are normally distributed and homoscedastic. When these assumptions are not met, the results from a classical moderation analysis can be misleading. For more reliable moderation analysis, this article proposes two robust methods with a two-level regression model when the predictors do not contain measurement error. One method is based on maximum likelihood with Student's t distribution and the other is based on M-estimators with Huber-type weights. An algorithm for obtaining the robust estimators is developed. Consistent estimates of standard errors of the robust estimators are provided. The robust approaches are compared against normal-distribution-based maximum likelihood (NML) with respect to power and accuracy of parameter estimates through a simulation study. Results show that the robust approaches outperform NML under various distributional conditions. Application of the robust methods is illustrated through a real data example. An R program is developed and documented to facilitate the application of the robust methods.  相似文献   
237.
Five studies investigated the relationship between individual-based relative deprivation (IRD) and prosocial behaviors. Study 1 found that income satisfaction, a concept closely related to IRD, was negatively associated with prosocial values across cultures. Study 2 found a negative association between IRD and prosocial aspirations among a sample of Chinese university students. Study 3 revealed a negative association between IRD and volunteer behaviors. In Studies 4 and 5, we found that laboratory-induced IRD decreased undergraduate students’ prosocial values and behaviors. Moreover, Study 5 also found that the tendency to prioritize self-interest over others’ mediated the effect of IRD on prosocial behaviors. Implications of these findings are discussed.  相似文献   
238.
Tungsten (W) is cited as a candidate first-wall material in fusion reactors owing to its outstanding thermal properties and erosion resistance. An important issue is that the energetic isotopes of hydrogen, tritium (T) and deuterium (D) and helium (He) particles damage the surface of W in fusion reactors. He particles cause more notable damage than D or T because the binding energy of defects and He is larger than that of defects and D or T. In this study, well-annealed W specimens were implanted with 5 keV He ions at room temperature and irradiation dosages of 1.0 × 1020 and 2.5 × 1021 ions/m2. Then, thermal desorption spectroscopy analysis was performed by heating the samples to 1973 K at a ramping rate of 0.5 K/s. Thermal desorption of He in the sample irradiated with a low dosage occurred at 1400 and 1960 K, whereas that in the sample irradiated with a high dosage occurred at 740, 1050 and 1500 K. According to the microstructures observed using transmission electron microscopy, both peaks in the former case were attributed to He de-trapping from irradiation to nduced helium-vacancy clusters of different sizes, whereas the peaks in the latter case were attributed to He de-trapping from surface defects, irradiation-induced dislocation loops and tiny helium-vacancy clusters, respectively.  相似文献   
239.
This study aimed to identify social‐psychological predictors of pro‐environmental consumption intention in rural China. To this end, a proposed conceptual model was tested by analyzing the survey data derived from 972 rural respondents in Jiangxi province in south‐eastern China. Results showed that the endorsement of traditional cultures (man–nature orientation and collectivism) was linked with pro‐environmental consumption behaviuor, but was mediated by intentions. Personal attitudes (environmental cognition and environmental affect) and reference groups influenced both intention and behaviour. The results also provided good evidence of the intention–behaviour relationship. These findings provided a better understanding of the process in which Chinese rural residents developed their pro‐environmental consumption behaviours.  相似文献   
240.
According to the CAD model of emotional responses to immorality, if an event violates the moral foundations of justice and harm, people will feel angry. However, the model is silent on whether the strength of association between anger and perceived injustice/harm is context‐dependent. Using a contextual priming paradigm, the current research shows that in China, the association between anger and perceived injustice/harm is stronger when work (vs family) and modern (vs traditional) contexts are primed. Specifically, we primed modernity versus traditionality (Experiment 1) and work experiences (Experiment 2) and measured the strength of association between justice/harm concerns and anger. The results show that: (i) the linkage between justice/harm concern and anger was stronger in the modernity priming condition than in the tradition priming or control conditions; and (ii) the linkage between justice/harm concern and anger was stronger in the work experience priming condition than in the control condition. In short, priming modern and work contexts strengthens the association between justice/harm concerns and anger, suggesting the strength of the morality–emotion link is context‐dependent.  相似文献   
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