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181.
The defense of offspring, termed maternal aggression, is a highly conserved behavior in mammals, including rodents. This study examined relative levels of maternal aggression in two closely related dwarf hamster species, Phodopus campbelli and P. sungorus, that normally inhabit high latitude, boreal environments. When tested with first litters and with the breeder male remaining with the female (for P. campbelli the male is necessary for successful rearing of offspring), both species exhibited high levels of maternal aggression with average duration of aggressive behavior>80 sec for a 10 min test. For P. sungorus, males are not required to rear offspring. P. sungorus females with either one or multiple litters (singly housed after impregnation) exhibited significantly higher levels of aggression (>300 sec) relative to females co‐housed with the sires. In terms of species differences in attack style, P. campbelli exhibited a boxing or clawing strategy for ~50% of total attack time, but for P. sungorus, this form of attack occurred<5% of the time. For P. sungorus, attacks to the vulnerable belly and flank constituted>90% of all attacks, but these regions were attacked ~50% of the time for P. campbelli. A survey of levels of maternal aggression of rodents in other genera suggests that maternal aggression in Phodopus is at the high end of the spectrum. Results of this study suggest that the presence of the breeder male may actually suppress aggression in P. sungorus. This fact, as well as its high level of aggression and its distant relationship to mice and rats, suggest P. sungorus as a possible model for future studies on the neurobiological basis of maternal aggression. The relationship between the high rates of maternal aggression and life history strategy in Phodopus is discussed. Aggr. Behav. 00:000–000, 2005. © 2005 Wiley‐Liss, Inc.  相似文献   
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183.
Building collaborative multidisciplinary mental health teams to boost student achievement has been a growing initiative in American schools since the 1970s. Marriage and Family Therapists (MFTs)joined those teams in 2008, when Connecticut became the first state to certify MFTs for schoolbased practice. This article chronicles the history of that collaboration and reports initial research into MFT school-based participation on those teams.  相似文献   
184.
Although the measurement of working memory capacity is crucial to understanding working memory and its interaction with other cognitive faculties, there are inconsistencies in the literature on how to measure capacity. We address the measurement in the change detection paradigm, popularized by Luck and Vogel (Nature, 390, 279-281, 1997). Two measures for this task-from Pashler (Perception & Psychophysics, 44, 369-378, 1988) and Cowan (The Behavioral and Brain Sciences, 24, 87-114, 2001), respectively-have been used interchangeably, even though they may yield qualitatively different conclusions. We show that the choice between these two measures is not arbitrary. Although they are motivated by the same underlying discrete-slots working memory model, each is applicable only to a specific task; the two are never interchangeable. In the course of deriving these measures, we discuss subtle but consequential flaws in the underlying discrete-slots model. These flaws motivate revision in the modal model and capacity measures.  相似文献   
185.
The role of epigenetic mechanisms in control of gene expression during mammalian development is well established. Associations between specific DNA or histone modifications and numerous neurodevelopmental and neurodegenerative disorders implies significant consequences of epigenetic dysregulation in both the developing and mature brain, the latter of which is the general focus of this review. Accumulating evidence suggests that epigenetic changes are involved in normal cognitive processes in addition to neurological and psychiatric disorders. Recent investigations into the regulation of epigenetic modifications in the adult brain have revealed novel and surprisingly dynamic mechanisms for controlling learning and memory-related behaviors as well as long-term synaptic plasticity. DNA methylation and histone acetylation have also been implicated in the modulation of basal synaptic transmission and the balance between excitation and inhibition in various brain regions. Studies have begun to uncover some of the alterations in gene expression that appear to mediate many of these effects, but an understanding of the precise mechanisms involved is still lacking. Nevertheless, the fundamental importance of epigenetic processes in influencing neuronal activity is becoming increasingly evident.  相似文献   
186.
Studies have demonstrated that maternal stress and perceptions of self-efficacy influence a mother's performance, affecting her ability to interact with her child and to understand and answer his needs. The purpose of this study was to evaluate maternal stress and the perception of self-efficacy in the mothers of infants who are cared for in child-care centers and belong to the poorest segment of the Chilean population. To this end, these aspects were studied in 121 low-income, high-social-risk mothers with children between the ages of 4 and 9 months. The final goal was to generate an explicative model of self-efficacy and maternal stress that considered characteristics of the family and the child. The results revealed that family characteristics - especially household size, per capita incomes and mother age - are more relevant for explaining maternal self-efficacy and stress. The findings and implications for practice are discussed.  相似文献   
187.
At the time of this writing, a widely publicized, waived-consent trial is underway. Sponsored by Northfield Laboratories, Inc. (Evanston, IL) the trial is intended to evaluate the emergency use of PolyHeme?, an oxygen-carrying resuscitative fluid that might prevent deaths from uncontrolled bleeding. The protocol allows patients in hemorrhagic shock to be randomized between PolyHeme? and saline in the field and, still without consent, randomized between PolyHeme? and blood after arrival at an emergency department. The Federal regulations that govern the waiver of consent restrict its applicability to circumstances where proven, satisfactory treatments are unavailable. Blood-the standard treatment for hemorrhagic shock-is not available in ambulances but is available in hospitals. The authors argue that the in-hospital stage of the study fails to meet ethical and regulatory standards.  相似文献   
188.
The present study sought to explore how women's life experiences influenced their beliefs, and how those beliefs in turn influenced feminist self-identification. Additionally, we sought to determine whether feminist self-identification led to increased collective action on behalf of women. Female participants (N?=?282) from two US college campuses and online listservs completed an online survey assessing feminist self-identification, collective action, and life experiences. Conservative, liberal, and radical beliefs were assessed as were evaluations of feminists. A structural equation model was used to explore these relationships; life experiences were found to influence women's beliefs, which in turn influenced feminist self-identification, which influenced collective action. We found that life experiences may serve as a catalyst for both feminist self-identification and collective action.  相似文献   
189.
The purpose of the paper is to reflect on value dilemmas in mental health consumer-run organizations and to discuss implications for research, policy, and practice. We review the roots of consumer-run organizations in the self-help movement and the psychiatric survivor liberation movement, focusing on the distinctive values espoused by consumer-run organizations. We also discuss evidence-based and value-based approaches to mental health policy formulation and mental health reform, noting the particular importance of value-based approaches and the role that consumer-run organizations can play in mental health reform. Based on our experiences conducting a participatory action research study of four mental health consumer-run organizations, we identify and examine several value dilemmas, discuss the lessons that we learned about these value dilemmas, and note their implications for future directions in research, policy, and practice.  相似文献   
190.
Intent Attributions and Aggression: A Study of Children and their Parents   总被引:1,自引:1,他引:0  
This research aimed to further clarify the relationship between children's self-reported hostile intent attributions (for ambiguous instrumental or relational provocations) and peer-reported aggression (physical and relational) in 500 fourth-grade children. In addition, we examined whether parents' intent attributions might predict children's intent attributions and aggression. Both parents (mothers and fathers) in 393 families completed intent attribution questionnaires. Results showed, consistent with past research, that boys' instrumental intent attributions were related to physical aggression. Children's relational intent attributions, however, were not associated with relational aggression. Contrary to expectations, most children responded with hostile intent attributions for relational provocations. Finally, in regard to parent-child connections, maternal intent attributions correlated with children's intent attributions whereas paternal intent attributions corresponded with children's relational aggression.  相似文献   
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