Infants of Depressed Mothers Show Reduced Gaze Activity During Mother–Infant Interaction at 4 Months

Gaze is one of the main means of communication in young infants, and it has been shown to be important for subsequent socio‐emotional and cognitive development. Maternal depression is a well‐known risk factor for disrupting mother–infant interactions, but findings regarding gaze behavior in infants of depressed versus nondepressed mothers have been ambiguous. In this study, we examined gaze duration and activity in a sample of 27 infants of mothers with postpartum depression (PPD) and 49 infants of nondepressed mothers. Maternal depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale, and diagnoses were confirmed in clinical interview. Infant gaze was assessed during 4‐month face‐to‐face interactions using continuous timed‐event coding with high temporal resolution. Although we found no differences in gaze duration, infants of PPD mothers had both significantly less Gaze On and also less Gaze Off events. Findings suggest that PPD is related to reduced gaze activity during mother–infant interaction in 4‐month‐olds. This reduced activity may have long‐term negative consequences for child development.     

Vocal Coordination During Early Parent–Infant Interactions Predicts Language Outcome in Infant Siblings of Children with Autism Spectrum Disorder

This study examined vocal coordination during mother–infant interactions in the infant siblings (high‐risk infants; HR) of children with autism spectrum disorder (ASD), a population at heightened risk for developing language delays (LDs). Vocal coordination between mothers and HR infants was compared to a group of low‐risk (LR; no first‐ or second‐degree relative with ASD) dyads and used to predict later language development. Nine‐month‐old infants were video‐taped at home playing with their mothers, and interactions were coded for the frequency and timing of vocalizations. Percent infant simultaneous speech was predictive of later LD, and dyads with LD infants were less coordinated with one another in average latency to respond than dyads with non‐delayed (ND) infants. The degree of coordination between mothers and infants on this variable predicted a continuous measure of language development in the third year. This research underscores the importance of understanding early development in the context of interaction.     

Individual Differences in Women's Salivary Testosterone and Estradiol Following Sexual Activity in a Nonlaboratory Setting

Objectives: The current study evaluated women's salivary testosterone and estradiol levels before and after exposure to sexual stimuli in a U.S. sex club. Methods: Behavioral data and salivary samples were collected from 19 women during semistructured interviews. Results: Findings demonstrate substantial individual differences in the magnitude and direction of women's hormonal changes following sexual activity. Conclusions: In an age of individualized medicine, these findings highlight the need to better understand factors shaping variation in physiological responses to sexual activity. Findings contribute to a relatively small and contradictory literature on women's hormonal responses to sexual stimuli.     

工业缝纫机针杆的气浮轴承性能数值计算与分析

为了对气浮针杆的小孔节流型轴承的支承性能进行研究,文章在建立数学模型的基础上,运用有限差分法对控 制方程进行数值有限差分的推导,利用MATLAB对针杆在低速和高速的情况下的压力分布进行了数值求解。结果表 明：气浮轴承能够较好地实现工业缝纫机的低速和高速情况下的气浮支承;双排节流小孔的压力分布承载效果比单排节 流小孔好;随着气浮针杆运动速度的变化双排节流小孔的气浮轴承的稳定性较好。对进一步深入对工业缝纫机针杆的 气浮支承研究具有指导意义。     

Parental Influence on Friendships Between Native and Immigrant Adolescents

Parental influence on friendships between native (N = 5,683) and immigrant (N = 3,371) adolescents (aged ± 15) was investigated with the CILS4EU data of pupils in German and Dutch school classes (N = 446) and parents. The researchers examined whether parents affect friendships across group boundaries by shaping the structural opportunities to establish out‐group friends and their children's out‐group attitudes. The results show that if parents have more out‐group friends and if they consider it less important to maintain in‐group traditions, their children have more out‐group friends. Part of this relationship is mediated by children's out‐group attitudes. Some evidence is found that the opportunity structure mediates the relationship between parental characteristics and adolescent out‐group friendship.     

Same-Gender Sexual Partnering: A Re-Analysis of Trend Data

Numerous studies have been carried out to estimate the prevalence of same-gender sexual behavior. Among studies conducted in recent years, few confirm the commonly quoted figure of 10%. Yet several studies in the early 2000s indicated that the prevalence of same-gender sex may be increasing, especially among women. This article reexamines the trends identified in previous research by using General Social Survey data from 1988 to 2010 and by focusing on multiple measures of same-gender sex over time. Results indicate that for both women and men the likelihood of having had a same-gender sexual partner since age 18 continued to increase through the 2000s, but that the likelihood of having had a same-gender sexual partner in both the past year and in the past five years leveled off for women and reversed for men. Results also indicate that the percentage of people reporting a pattern of predominantly same-gender sexual behavior has neither increased nor decreased over time. A similar result was found among persons who reported being in a same-gender sexual relationship. Overall, results paint a more complex picture than prior studies in characterizing trends in same-gender sexual behavior.