Language experiences and vocabulary development in Dominican and Mexican infants across the first 2 years

We longitudinally investigated parental language context and infants' language experiences in relation to Dominican American and Mexican American infants' vocabularies. Mothers provided information on parental language context, comprising measures of parents' language background (i.e., childhood language) and current language use during interviews at infants' birth. Infants' language experiences were measured at ages 14 months and 2 years through mothers' reports of mothers' and fathers' engagement in English and Spanish literacy activities with infants and mothers' English and Spanish utterances during videotaped mother-infant interactions. Infants' vocabulary development at 14 months and 2 years was examined using standardized vocabulary checklists in English and Spanish. Both parental language context and infants' language experiences predicted infants' vocabularies in each language at both ages. Furthermore, language experiences mediated associations between parental language context and infants' vocabularies. However, the specific mediation mechanisms varied by language.     

Female facial appearance and health

The current study addressed whether rated femininity, attractiveness, and health in female faces are associated with numerous indices of self-reported health history (number of colds/stomach bugs/frequency of antibiotic use) in a sample of 105 females. It was predicted that all three rating variables would correlate negatively with bouts of illness (with the exception of rates of stomach infections), on the assumption that aspects of facial appearance signal mate quality. The results showed partial support for this prediction, in that there was a general trend for both facial femininity and attractiveness to correlate negatively with the reported number of colds in the preceding twelve months and with the frequency of antibiotic use in the last three years and the last twelve months. Rated facial femininity (as documented in September) was also associated with days of flu experienced in the period spanning the November-December months. However, rated health did not correlate with any of the health indices (albeit one marginal result with antibiotic use in the last twelve months). The results lend support to previous findings linking facial femininity to health and suggest that facial femininity may be linked to some aspects of disease resistance but not others.     

Irradiation-enhanced twin boundary migration in BCC Fe

The effects of irradiation on twin boundary migration in BCC Fe are studied by atomistic simulations. It is found that under the applied shear strain–stress, thermal spikes may create twinning dislocation loops (TDLs) at twin boundaries, so triggering twinning. Irradiation-generated clusters of point defect at twin boundaries may act as sources to nucleate TDLs. When a vacancy loop intersects with a twin boundary, the critical stress to activate a TDL is less than half of that required for a defect-free twin boundary.     

Structure of Al–Co–Ni pentagonal quasicrystal studied by HAADF-STEM and ab initio calculations

Using a combination of atomic-resolution high-angle annular dark-field (HAADF) Z-contrast imaging and ab initio calculations, atomic models of clusters 2 nm in diameter and 0.8 nm in height are proposed for the Al–Co–Ni pentagonal quasicrystal. This quasicrystal has 5-fold symmetry (the so-called 5f state) without superstructures, and is one of numerous modifications of the Al–Co–Ni decagonal quasicrystal. HAADF results reveal that the two-dimensional quasi-periodic lattice contains mainly Penrose pentagonal tiling. The centres within the decorated pentagonal tiles, i.e. the so-called pentagonal super-clusters, show structural characteristics having both a satellite-orbit shape and a pentagon-symmetry shape. The proposed atomic models, based directly on the HAADF images, are subjected to ab initio total energy calculations. After relaxation, the calculations demonstrate that the models with 5-fold symmetry are energetically more favourable than those with 10-fold symmetry.     

Tensile deformation behaviour of Zr-based glassy alloys

This paper presents a study of the deformation behaviour of a glassy phase in two Zr-based alloys, Zr₆₅Ni₁₀Cu₅Al_7.5Pd_12.5 and Zr₆₅Al_7.5Ni₁₀Pd_17.5, performed in situ in a transmission electron microscope. In contrast to the case of shear localisation and formation of 10–20 nm thick shear bands in deformed bulk glassy samples studied earlier, it is found that in thin (electron-transparent) samples the glassy phase in front of a crack deforms more homogeneously and no nanocrystallisation takes place. The reasons for such behaviour are discussed. According to the observed results, one can conclude that the studied metallic glasses can be intrinsically ductile in submicrometre-sized volumes.     

Social Learning Strategies in Networked Groups

When making decisions, humans can observe many kinds of information about others' activities, but their effects on performance are not well understood. We investigated social learning strategies using a simple problem‐solving task in which participants search a complex space, and each can view and imitate others' solutions. Results showed that participants combined multiple sources of information to guide learning, including payoffs of peers' solutions, popularity of solution elements among peers, similarity of peers' solutions to their own, and relative payoffs from individual exploration. Furthermore, performance was positively associated with imitation rates at both the individual and group levels. When peers' payoffs were hidden, popularity and similarity biases reversed, participants searched more broadly and randomly, and both quality and equity of exploration suffered. We conclude that when peers' solutions can be effectively compared, imitation does not simply permit scrounging, but it can also facilitate propagation of good solutions for further cumulative exploration.     

公共资源困境中领导对群体成员合作行为的影响

过去社会困境的领导研究大多都以被试作为领导, 发现贴上领导标签后, 被试倾向于拿取更多的公共资源, 从而有碍公共利益的实现。本研究指出, 如果领导的背叛行为能够使群体成员表现出自我节制行为的话, 那么设置领导则有可能促进公共利益的实现。研究通过三个实验, 考察领导与普通群体成员不同的行为方式以及领导的产生方式对群体成员行为的影响, 并检验公平理论和社会认同理论的解释力。研究结果表明, 领导表现出背叛行为时, 被试表现出更多的自我节制行为; 指派领导及外群体选举领导背叛时, 被试表现出更多的自我节制行为, 验证了社会认同理论的正确性。     

Narrative organisation at encoding facilitated children's long-term episodic memory

This study examined the effect of narrative organisation at encoding on long-term episodic memory in a sample of five- to seven-year-old children (N = 113). At an initial interview, children were asked to narrate a story from a picture book. Six months later, they were interviewed again and asked to recall the story and answer a series of direct questions about the story. Children who initially encoded more information in narrative and produced more complete, complex, cohesive and coherent narratives remembered the story in greater detail and accuracy following the six-month interval, independent of age and verbal skills. The relation between narrative organisation and memory was consistent across culture and gender. These findings provide new insight into the critical role of narrative in episodic memory.     

Main and interactive effects of social support in predicting mental health symptoms in men and women following military stressor exposure

Abstract

Evidence across a multitude of contexts indicates that social support is associated with reduced risk for mental health symptoms. More information is needed on the effectiveness of different sources of support, as well as sex differences in support. Associations between social support from two sources – the military unit and friends and family – and mental health symptoms were examined in a study of 1571 Marine recruits assessed at the beginning and end of a highly stressful 13-week training program. Military social support buffered the stressor exposure–posttraumatic stress symptomatology (PTSS) relationship, whereas the relationship between stressor exposure and PTSS was highest when civilian social support was high. Further inspection of the interactions revealed that military support was most important at high levels of stressor exposure. Sex differences in the relationship between social support and symptoms were found, such that support from military peers was associated with lower levels of PTSS for men, whereas civilian support was associated with lower PTSS for women. While civilian social support was associated with lower levels of depression symptom severity in both women and men, the relationship was stronger for women. Reviewed implications focus on the importance of considering the recipient, source, and context of social support.     

Developing an instrument to measure physical activity related self-worth in women: Rasch analysis of the Women's Physical Activity Self-Worth Inventory (WPASWI)

ObjectivesThe objective of this study is to report on the development of an instrument to assess non-physical aspects of physical activity (PA)-related self-worth (SW).MethodsThree hundred thirty five women (mean age = 36.69 ± 15.94 yrs, BMI = 24.87 ± 4.56) completed the Women's Physical Activity Self-Worth Inventory (WPASWI), General SW Scale, and a PA Questionnaire. Rasch analysis was used to evaluate the WPASWI.ResultsThree PA-related SW subscales were identified: PA Knowledge (16 items), PA Emotional (13 items), and PA Social (8 items). Rasch analysis supported construct validity, and items demonstrated acceptable internal consistency (Cronbach's alpha = 0.90, 0.87 and 0.72) and test-re-test reliability (r = 0.79, 0.70, 0.81). Women who reported regular PA participation had higher PA Knowledge, PA Emotional, PA Social, and General SW than those who reported some or no PA (p < 0.01) and correlations between Knowledge, Emotional, and Social SW subscales and General SW were 0.207, 0.130, and 0.220, respectively. PA Knowledge and PA Emotional SW had stronger correlations with PA (r = 0.344, 0.273, respectively) than did General SW (r = 0.133).ConclusionsThe WPASWI demonstrated good internal consistency, reliability, construct validity and a stronger relationship with PA than a General SW instrument.