TGF-β1 in Aplysia: Role in Long-Term Changes in the Excitability of Sensory Neurons and Distribution of TβR-II-Like Immunoreactivity

Exogenous recombinant human transforming growth factor β-1 (TGF-β1) induced long-term facilitation of Aplysia sensory-motor synapses. In addition, 5-HT-induced facilitation was blocked by application of a soluble fragment of the extracellular portion of the TGF-β1 type II receptor (TβR-II), which presumably acted by scavenging an endogenous TGF-β1-like molecule. Because TβR-II is essential for transmembrane signaling by TGF-β, we sought to determine whether Aplysia tissues contained TβR-II and specifically, whether neurons expressed the receptor. Western blot analysis of Aplysia tissue extracts demonstrated the presence of a TβR-II-immunoreactive protein in several tissue types. The expression and distribution of TβR-II-immunoreactive proteins in the central nervous system was examined by immunohistochemistry to elucidate sites that may be responsive to TGF-β1 and thus may play a role in synaptic plasticity. Sensory neurons in the ventral–caudal cluster of the pleural ganglion were immunoreactive for TβR-II, as well as many neurons in the pedal, abdominal, buccal, and cerebral ganglia. Sensory neurons cultured in isolation and cocultured sensory and motor neurons were also immunoreactive. TGF-β1 affected the biophysical properties of cultured sensory neurons, inducing an increase of excitability that persisted for at least 48 hr. Furthermore, exposure to TGF-β1 resulted in a reduction in the firing threshold of sensory neurons. These results provide further support for the hypothesis that TGF-β1 plays a role in long-term synaptic plasticity in Aplysia.     

Achievement motivation in the social context: Implicit and explicit Hope of Success and Fear of Failure predict memory for and liking of successful and unsuccessful peers

The authors examined relations between implicit and explicit Hope of Success (HS) and Fear of Failure (FF) and memory and liking for successful and unsuccessful peers. Implicit motives were expected to predict memory and explicit motives to predict liking of peers. Results from 106 American and 79 Singaporean students supported the implicit–explicit motive distinction as well as a link between HS and the successful peer and between FF and the unsuccessful peer. In both samples, explicit HS predicts liking while implicit HS predicts memory about the successful peer, and implicit FF predicts memory about the unsuccessful peer. Findings indicate achievement motives affect interest in and reaction towards peers and provide evidence for differential validity of implicit and explicit motives.     

大学校园压力的类型和特点

本研究有两个主要目的：第一,探讨大学校园压力的类型;第二,分析大学校园压力的特点。研究分三个步骤,第一个步骤(研究一)采用开放式问卷方法探讨大学校园的主要压力源。第二个步骤(研究二)通过对开放式问卷的结果进行因素分析,确定压力类型。第三个步骤(研究三)采用量表测试方法分析大学校园压力的特点。主要测量工具为《大学生压力量表》。被试取自北京市两所高校的一至三年级大学生,共1295人。结果显示：大学校园压力的主要类型为：学习烦扰,个人烦扰和消极生活事件。大学校园压力的主要特点是：日常烦扰所产生的压力为主要压力,而突发性消极事件并非大学生压力的主要来源。     

The impact of stress on the life history strategies of African American adolescents: cognitions, genetic moderation, and the role of discrimination

The impact of 3 different sources of stress--environmental, familial (e.g., low parental investment), and interpersonal (i.e., racial discrimination)--on the life history strategies (LHS) and associated cognitions of African American adolescents were examined over an 11-year period (5 waves, from age 10.5 to 21.5). Analyses indicated that each one of the sources of stress was associated with faster LHS cognitions (e.g., tolerance of deviance, willingness to engage in risky sex), which, in turn, predicted faster LHS behaviors (e.g., frequent sexual behavior). LHS, then, negatively predicted outcome (resilience) at age 21.5 (i.e., faster LHS → less resilience). In addition, presence of the risk ("sensitivity") alleles of 2 monoamine-regulating genes, the serotonin transporter gene (5HTTLPR) and the dopamine D4 receptor gene (DRD4), moderated the impact of perceived racial discrimination on LHS cognitions: Participants with more risk alleles (higher "sensitivity") reported faster LHS cognitions at age 18 and less resilience at age 21 if they had experienced higher amounts of discrimination and slower LHS and more resilience if they had experienced smaller amounts of discrimination. Implications for LHS theories are discussed.     

Males Prefer Younger Females: Age Preference Among Online Daters in the Dominican Republic

Previous research has found that online daters show a trend in age preference, with males seeking females younger than themselves and females seeking males older than themselves. These studies covered a wide geographic area but not in the Caribbean. To contribute to the literature, we examine online daters’ age preferences in the Dominican Republic. Our statistical analyses show that similar gendered age preferences exist among Dominican online daters even after controlling for their ages. On average, Dominican males prefer younger partners and the reverse is true for females. While there might be cultural differences in different countries affecting the extent and degree of age preferences, the consistent difference by sex underscores the challenges faced by older females in the online dating market.     

The coordination of compensatory tracking and anticipatory timing tasks

Two experiments investigated the presence of a coordination factor in a task consisting of compensatory tracking and anticipatory timing components. The task (Intercept task) resembles a computer game in which a rocket must be aimed and fired to shoot an incoming missile. The studies were designed to determine if a coordinating ability exists above and beyond the abilities needed to perform the component tasks alone. We also investigated the nature of coordination abilities through correlations with other types of coordination tasks and measures of intelligence. Is coordination a general cognitive ability that contributes to performance in a wide range of coordination tasks, or is coordination ability task specific? Multiple regression analyses indicated the existence of a coordination ability in the Intercept task. This coordination ability, however, was shown to be unrelated to the coordination of visual and linguistic processing and to psychometric measures of intelligence as assessed by the Armed Services Vocational Aptitude Battery (ASVAB). Coordination of visual and linguistic processing correlated with a component of the ASVAB measuring perceptual speed. We conclude that, although the ability to integrate separate components of a complex task draws on a coordination ability, this ability is domain specific and thus varies depending on the nature of the component tasks.     

The Moderating Role of Verbal Aggression on the Relationship Between Parental Feedback and Peer Status Among Children with ADHD

We examined associations between children's sociometric status and (a) observed parental feedback as well as (b) child aggression. Participants were 94 children ages 6-10 (64 male; 44 with ADHD) and their parents. Children's peer status, parental feedback to their children, and child aggression were all assessed during lab-based playgroups of four children and their parents. Parent criticism in front of the child's peers was associated with the child receiving more negative ("disliked") and fewer positive ("liked") nominations, but only for children who displayed aggression; this interaction applied almost exclusively to children with ADHD. Parent praise in front of peers was associated with fewer negative nominations when children displayed low levels of aggression, but more at higher levels. Additional analyses revealed that relationships did not exist in the full sample between privately-given parental feedback and children's peer status. Processes by which peers use overheard adult feedback to inform their assessments of children are discussed.     

Why do(n't) your partner's efforts at self-improvement make you happy? An implicit theories perspective

People often try to improve their interpersonal skills to satisfy romantic partners. However, when and why a partner appreciates these efforts is an important but underaddressed question. The present research explored how people's theories that interpersonal abilities are either fixed entities or can be changed incrementally affect their responses to relationship partner's efforts at self-improvement. Study 1 validated a new measure for these theories and showed that, compared to the former entity theorists, the latter incremental theorists were less likely to attribute recalled instances of partners' negative behaviors to dispositional causes and perceive these behaviors as fixed and stable. An experiment that induced these different implicit theories (Study 2) and a longitudinal study (Study 3) further demonstrated that perceptions of partners' self-improvement efforts led to greater increases in relationship security and quality among incremental than among entity theorists. How implicit theories may shape the interpersonal dynamics of self-improvement is discussed.     

Contesting and Maintaining Hegemonic Masculinities: Gay Asian American Men in Mate Selection

Masculinity is a prized commodity in mate selection among gay men. However, few studies systematically examine how gay Asian American men interpret their form of masculinity in the context of mate selection. Using data from in-depth interviews with 37 Asian Americans, I study how they interpret and negotiate their form of masculinity within a racialized gender hierarchy. The results show gay Asian American men maintain the hegemonic masculinity frame in the negotiation of their desirability and desires. Concurrently, they also attempt to reframe their masculinity to contest the subordination of their form of masculinity. Ironically, their alternate frame still maintains a gendered hierarchy whereby masculinity is still preferred over femininity, even as it contests the racialized hegemonic masculinity frame.     

Cortisol Awakening Response as an Index of Mental Health and Well-Being in Adolescents

Physiological measures provide a useful complement to self-report indices of mental health and well-being. The cortisol awakening response (CAR) has been associated with mental distress, but less consistently so with positive functioning. In this study, the utility of two CAR indices as a measure of the full spectrum of mental health and well-being in a sample of healthy adolescents was explored. Forty-seven adolescents (14M, 33F; mean age 13.89, SD = .73) completed questionnaires on mental distress and positive functioning, and provided three saliva samples for cortisol analysis as well as demographic and life event information. Correlational analyses revealed that both absolute CAR (CARi) and area under the curve during awakening (CAR_AUC) indices correlated positively with measures of mental distress, and inversely with measures of positive functioning. When the significant life events score was controlled, moderate to strong effects were maintained with negative and positive affect, mental well-being, satisfaction with life and perceived social support from significant others. These findings provide the first data confirming that CAR is a reliable index of positive functioning in healthy adolescents.