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131.
Despite the childhood benefits gained from engaging in adequate physical activity, Australian preschool-aged children are reported to spend little time being physically active. Parental planning is important to engaging preschool-aged children in physical activity. Behavioral barriers, normative support, and self-efficacy have been identified as key determinants of parental decision making. However, the interplay among these factors is not well understood. The aim of this study was to examine the role of these psycho-social variables on parents’ planning and behavior for their preschool-aged children’s physical activity. A survey at two points in time was conducted in 208 Australian parents (n?=?139 mothers, M age?=?36.43 years, SD?=?5.04; n?=?69 fathers, M age?=?36.33 years, SD?=?6.5) of children aged between 2 and 5 years. A conditional process analysis was conducted that integrates mediation and moderation analyses. The results showed that planning and behavioral barriers predicted behavior, with a moderation effect also identified; more planning helped compensate for barriers. Normative support predicted both planning and behavior. In addition, an interaction between normative support and self-efficacy emerged. Parents with high self-efficacy engaged in high levels of planning, independent of normative support. Low self-efficacy with low normative support resulted in the lowest amount of planning; however, in the absence of normative support a high level of self-efficacy could compensate for it. Current findings provide avenues for future research to develop interventions to test the efficacy of these mechanisms in promoting parents’ ability to ensure preschool-aged children are active.  相似文献   
132.
ABSTRACT

The differentiation of trait anxiety and depression in nonclinical and clinical populations is addressed. Following the tripartite model, it is assumed that anxiety and depression share a large portion of negative affectivity (NA), but differ with respect to bodily hyperarousal (specific to anxiety) and anhedonia (lack of positive affect; specific to depression). In contrast to the tripartite model, NA is subdivided into worry (characteristic for anxiety) and dysthymia (characteristic for depression), which leads to a four-variable model of anxiety and depression encompassing emotionality, worry, dysthymia, and anhedonia. Item-level confirmatory factor analyses and latent class cluster analysis based on a large nation-wide representative German sample (N?=?3150) substantiate the construct validity of the model. Further evidence concerning convergent and discriminant validity with respect to related constructs is obtained in two smaller nonclinical and clinical samples. Factors influencing the association between components of anxiety and depression are discussed.  相似文献   
133.
Research on human causal induction has shown that people have general prior assumptions about causal strength and about how causes interact with the background. We propose that these prior assumptions about the parameters of causal systems do not only manifest themselves in estimations of causal strength or the selection of causes but also when deciding between alternative causal structures. In three experiments, we requested subjects to choose which of two observable variables was the cause and which the effect. We found strong evidence that learners have interindividually variable but intraindividually stable priors about causal parameters that express a preference for causal determinism (sufficiency or necessity; Experiment 1). These priors predict which structure subjects preferentially select. The priors can be manipulated experimentally (Experiment 2) and appear to be domain‐general (Experiment 3). Heuristic strategies of structure induction are suggested that can be viewed as simplified implementations of the priors.  相似文献   
134.
Males taken into police custody for reported spouse abuse (n = 19) and a matched control group (n = 19) were asked to describe the drinking habits of their parents and the extent of intra-family violence witnessed by them as children. The retrospective data were compared to the participant's own present alcohol use and aggressiveness (CTS). Excessive paternal drinking and intra-family violence were recalled significantly more often by the spouse abusers than by the controls. A latent structure model suggested that the accumulated violence history was less well predicted by either paternal violence or present aggressiveness than by the direct and indirect effects related to drinking. Context-specific social learning could explain why the parental drunken violence behavior pattern witnessed by the child was repeated by the adult spouse abuser. Aggr. Behav. 23:239–243, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
135.
20–40% of the patients in general practices, as well as in different departments in hospitals, suffer from somatoform diseases. 70% of these patients have pain as their main complaint. The present treatment manual is the first disease-specific, psychodynamically oriented group-treatment for these patients. Compared to other psychodynamic treatment settings this therapy is a short and cost-effective approach to treat these patients. It is based on a so-called psychodynamic-interactional group psychotherapy and focuses on disease-specific parts of the problem, as well as on psychic and interpersonal problems resulting from adverse childhood experiences. Over a period of six months 7 to 9 patients are treated in 40 group therapy sessions. Two weekly meetings are held during the first four months and one weekly session is held during the last two months. The concept contains psycho-educational elements, the discussion and formulation of individual treatment goals as well as work with a psychodynamic and relationship- oriented treatment focus. The efficacy of this concept is planned to be evaluated in a randomised, controlled clinical trial, including two treatment conditions and one control condition. One of the two treatment conditions is, beneath the concept already discussed, a cognitive behavioural group therapy.  相似文献   
136.
137.
The NMDA receptor (NMDAR) subunit GluN1 is an obligatory component of NMDARs without a known functional homolog and is expressed in almost every neuronal cell type. The NMDAR system is a coincidence detector with critical roles in spatial learning and synaptic plasticity. Its coincidence detection property is crucial for the induction of hippocampal long-term potentiation (LTP). We have generated a mutant mouse model expressing a hypomorph of the Grin1N598R allele, which leads to a minority (about 10%) of coincidence detection-impaired NMDARs. Surprisingly, these animals revealed specific functional changes in the dentate gyrus (DG) of the hippocampal formation. Early LTP was expressed normally in area CA1 in vivo, but was completely suppressed at perforant path-granule cell synapses in the DG. In addition, there was a pronounced reduction in the amplitude of the evoked population spike in the DG. These specific changes were accompanied by behavioral impairments in spatial recognition, spatial learning, reversal learning, and retention. Our data show that minor changes in GluN1-dependent NMDAR physiology can cause dramatic consequences in synaptic signaling in a subregion-specific fashion despite the nonredundant nature of the GluN1 gene and its global expression.According to Hebb''s postulate, neurons require a molecular mechanism to detect synchronous activity in order to change the strength of synaptic connectivity (Hebb 1949). NMDA receptors (NMDARs) are molecular coincidence detectors, and selective NMDAR antagonists block the induction of long-term potentiation (LTP) in both the dentate gyrus (DG) and CA1 regions of the hippocampus (Bliss and Collingridge 1993; Martin et al. 2000). NMDARs have been long known for their role in spatial learning, but more recently have been implicated in other forms of cognitive function and dysfunction (Gruart et al. 2006; Whitlock et al. 2006; Castner and Williams 2007; Kristiansen et al. 2007; Wilson and Linster 2008).Neuronal NMDARs are hetero-tetrameric ligand-gated ion channels typically comprised of two types of subunits. Two copies of the mandatory GluN1 subunit (or NR1 subunit [Collingridge et al. 2009] encoded by Grin1) are associated with two copies from the GluN2 family, GluN2A–D (or NR2A–D). The GluN1 subunit is expressed ubiquitously both spatially and temporally throughout the developing and adult brain. Global knockout mice models of the GluN1 subunit are postnatally lethal within hours after birth (Forrest et al. 1994; Li et al. 1994), and cell-specific GluN1 mice knockouts (Tsien et al. 1996; Nakazawa et al. 2002; McHugh et al. 2007; Niewoehner et al. 2007) have provided insights on how specific synapses and regional neuronal networks are dependent on NMDAR function.The early postnatal lethality of the global GluN1 knockout is in contrast to the null mutants of the four AMPA receptor genes and other major synaptic proteins, such as αCaMKII (Silva et al. 1992a,b; Jia et al. 1996; Zamanillo et al. 1999; Meng et al. 2003). This can be at least partially explained by the absence of any close GluN1 homologs, which could functionally compensate for the absence of the GluN1 subunit. Recombinant expression studies defined the GluN1 subunit as a mandatory component of NMDARs. This constellation provides a specific opportunity to test whether different local neuronal subnetworks are affected differentially by mutant Grin1 alleles associated with subtle alterations of the functional properties of NMDARs.GluN1 subunits with the N598R point mutation (GluN1R) yield functional NMDARs that are Mg2+ insensitive and Ca2+ impermeable (Burnashev et al. 1992; Mori et al. 1992). The Grin1N598R allele that codes for GluN1R subunits is a gain-of-function mutation that is dominant lethal, even in heterozygous and hemizygous lines (Single et al. 2000; Rudhard et al. 2003). NMDARs with GluN1R subunits do not act as coincidence detectors and, interestingly, mice expressing exclusively the GluN1R allele lack whisker-related pattern formation in the neonate brainstem (Rudhard et al. 2003).To investigate the functional importance of GluN1 subunits with the N598R point mutation, we took advantage of the generation of a variant mutant line of mice (GluN1Rneo/+) expressing a minority (around 10%) of these mutant NMDARs. Even though the majority of the NMDARs are normal, all neurons expressing NMDARs will contain a subset of receptors carrying this mutation.Therefore, this mouse model is an ideal candidate to study the impact of subtle alterations of NMDAR function on different neuronal networks, such as those comprising the hippocampal formation.Studies examining region-specific targeted disruption of GluN1 expression in subregions of the hippocampus have revealed subtle yet important contributions of this NMDAR subunit in synaptic plasticity and spatial learning and memory. CA1-restricted knockout of GluN1 expression in the hippocampus caused impaired spatial learning and memory as well as reduced CA1-LTP (Tsien et al. 1996). In the case of the disruption of GluN1 expression in the DG region of the hippocampus, more subtle behavioral impairments were apparent, including the inability to discriminate between two similar contexts (pattern separation) and deficits in spatial working memory despite normal LTP in the CA1 region (McHugh et al. 2007; Niewoehner et al. 2007).Our GluN1Rneo/+ mice differ from the region-specific GluN1 mutant mice in that they express the mutant hypomorph at the same level in different subregions of the hippocampus. Interestingly, we found that this allele leads to substantial differences in short- and long-term plasticity between area CA1 and the DG of the hippocampus. The specific impairment in the DG was accompanied by impaired spatial recognition, spatial learning, reversal learning, and retention. Our data establish the possibility of a circuit-specific phenotype caused by a mutant variant of a globally expressed major nonredundant synaptic protein.  相似文献   
138.
This research examined the impact of a change in school diversity on school children's intergroup relations. A longitudinal survey tracked 551 White British and Asian British students (Mage = 11.32) transitioning from elementary (time 1) to secondary (time 2) school in an ethnically segregated town in the United Kingdom. We estimated a multivariate, multilevel model. A cross-sectional comparison of segregated schools and a mixed elementary school at time 1 revealed that both Asian and White British in the mixed school reported more positive intergroup relations. A longitudinal analysis found that the transition from segregated elementary to mixed secondary schools was associated with Asian British developing more positive intergroup relations. White British reported overall less positive intergroup relations, although only trust decreased; evidence from other measures remains inconclusive. The findings are important for understanding early stages of diversity exposure, and the impact of changing diversity levels on majority and minority groups.  相似文献   
139.
Concentrations of ethanol, testosterone, cortisol, and glucose were determined in serum obtained from 16 males taken into police custody after incidents of spouse abuse. The mean blood ethanol level at the time of arrest was 33.3 ± 2.6 mM. Serum testosterone levels were significantly lower and cortisol levels higher at the time of police intervention (within 1 hour of the incident) compared to control data collected later from the subjects when sober. Offenders did not differ from a group of nonviolent pub patrons at similar blood ethanol levels (35.9 ± 4.5 mM) with respect to serum testosterone, cortisol, or glucose, but their sober state cortisol and glucose concentrations were significantly higher compared to a control group of nonalcoholic men. Intoxication or acute hormonal changes were thus not specifically associated with violent behaviour. Provocative cues, however, may have been more frequent in the offender families, as Straus Conflict Tactics data showed that offenders and victims resorted to verbal aggression significantly more often than control families. The significantly elevated cortisol and glucose concentrations in offenders when sober compared to nonviolent controls could be viewed as direct effects of life stress, or as indirect effects of stress mediated by learned escape drinking. Excessive drinking as well as spouse abuse could be maladaptive coping strategies that principally serve to maintain the status quo, physiologically as well as psychologically. © 1992 Wiley-Liss, Inc.  相似文献   
140.
This paper provides an account of the closure conditions that apply to sets of subvening and supervening properties, showing that the criterion that determines under which property-forming operations a particular family of properties is closed is applicable both to the finitary and to the infinitary case. In particular, it will be established that, contra Glanzberg, infinitary operations do not give rise to any additional difficulties beyond those that arise in the finitary case.  相似文献   
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