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61.
The paper reviews a number of approaches for handling restricted quantification in relevant logic, and proposes a novel one. This proceeds by introducing a novel kind of enthymematic conditional.  相似文献   
62.
Capacity is a complex construct that lacks definitional clarity. Little has been done to define capacity, explicate components of capacity, or explore the development of capacity in prevention. This article represents an attempt to operationalize capacity and distinguish among types and levels of capacity as they relate to dissemination and implementation through the use of a taxonomy of capacity. The development of the taxonomy was informed by the capacity literature from two divergent models in the field: research-to-practice (RTP) models and community-centered (CC) models. While these models differ in perspective and focus, both emphasize the importance of capacity to the dissemination and sustainability of prevention innovations. Based on the review of the literature, the taxonomy differentiates the concepts of capacity among two dimensions: level (individual, organizational, and community levels) and type (general capacity and innovation-specific capacity). The proposed taxonomy can aid in understanding the concept of capacity and developing methods to support the implementation and sustainability of prevention efforts in novel settings.  相似文献   
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This review traces the development of counseling theory in relation to the philosophical constructs of free will and determinism. Problems associated with free will are discussed, and an analysis of related theoretical trends and convergent paradigms is provided. Results indicate that (a) no major theory of counseling addresses the free will versus determinism problem or includes indeterminate free will as a component; (b) no grand, comprehensive theory of counseling currently exists; and (c) recent findings relating to free will suggest the need for research along theoretical lines of inquiry. The relevance of such research to counseling professionals is emphasized.  相似文献   
65.
Activation of the N-methyl-d-aspartate receptor (NMDAR) glycine site has been shown to accelerate adaptive forms of learning that may benefit psychopathologies involving cognitive and perseverative disturbances. In this study, the effects of increasing the brain levels of the endogenous NMDAR glycine site agonist D-serine, through the genetic inactivation of its catabolic enzyme D-amino acid oxidase (DAO), were examined in behavioral tests of learning and memory. In the Morris water maze task (MWM), mice carrying the hypofunctional Dao1G181R mutation demonstrated normal acquisition of a single platform location but had substantially improved memory for a new target location in the subsequent reversal phase. Furthermore, Dao1G181R mutant animals exhibited an increased rate of extinction in the MWM that was similarly observed following pharmacological administration of D-serine (600 mg/kg) in wild-type C57BL/6J mice. In contextual and cued fear conditioning, no alterations were found in initial associative memory recall; however, extinction of the contextual fear memory was facilitated in mutant animals. Thus, an augmented level of D-serine resulting from reduced DAO activity promotes adaptive learning in response to changing conditions. The NMDAR glycine site and DAO may be promising therapeutic targets to improve cognitive flexibility and inhibitory learning in psychiatric disorders such as schizophrenia and anxiety syndromes.The N-methyl-d-aspartate receptor (NMDAR) has an important role in excitatory neurotransmission and contributes to numerous brain processes, including synaptic plasticity, learning, and memory formation (Nicoll 2003). Activation of NMDARs requires membrane depolarization in addition to concurrent binding of glutamate to NMDAR2 (NR2) and glycine to the NMDAR1 (NR1) subunit (Johnson and Ascher 1987; Clements and Westbrook 1991). D-serine has also been shown to be an endogenous co-agonist for the NR1 glycine site, acting with high selectivity and a potency similar to or greater than that of glycine (Matsui et al. 1995). In the brain, the localization of D-serine closely resembles that of NMDARs (Schell et al. 1997), and D-serine has been reported to be the predominant physiologic co-agonist for the maintenance of NMDAR-mediated currents in the hippocampus, retina, and hypothalamus (Mothet et al. 2000; Yang et al. 2003). Moreover, in vivo studies have demonstrated that the NMDAR glycine site is not saturated at the synapses of several brain regions (Fuchs et al. 2005). Consequently, increasing D-serine levels may modulate neurotransmission and behavioral responses reliant on NMDAR activity.The NMDAR glycine site has been implicated in the pathophysiology and treatment of a number of psychiatric conditions (Coyle and Tsai 2004; Millan 2005). Blockade of the NMDAR with noncompetitive antagonists like phencyclidine results in the production and exacerbation of schizophrenic-like symptoms in humans and animals (Javitt and Zukin 1991; Krystal et al. 1994). Genetic studies have associated genes that mediate D-serine synthesis and degradation with a vulnerability to schizophrenia, and levels of D-serine are decreased in the CSF and serum of schizophrenic patients (Chumakov et al. 2002; Hashimoto et al. 2003, 2005; Schumacher et al. 2004; Morita et al. 2007). These observations prompted clinical trials with direct and indirect activators of the NMDAR glycine site, including D-serine, and improvements were revealed when these compounds were added to conventional antipsychotic regimes, particularly with the negative and cognitive symptoms of schizophrenia (Tsai et al. 1998; Coyle and Tsai 2004; Heresco-Levy et al. 2005). Furthermore, altered NMDAR activation has also been shown to affect extinction, a learning process that may be of benefit in anxiety illnesses, such as post-traumatic stress syndrome and obsessive-compulsive disorder (Davis et al. 2006). In rodents, extinction was shown to be impaired following inhibition of NMDARs in contextual fear conditioning, inhibitory avoidance, and eyeblink conditioning tasks (Kehoe et al. 1996; Lee and Kim 1998; Szapiro et al. 2003). In contrast, the partial NMDAR agonist D-cycloserine facilitated the extinction of fear memories in rodents and individuals with phobias and other anxiety disorders (Ressler et al. 2004; Ledgerwood et al. 2005; Norberg et al. 2008). Thus, the NMDAR glycine site and its related modulatory proteins may be important targets for the amelioration of psychopathologies involving cognitive dysfunction and maladaptive behaviors.Endogenous levels of D-serine in the brain are regulated by its catabolic enzyme, D-amino acid oxidase (DAO); by the D-serine synthesis enzyme, serine racemase (Srr); and by neuronal and glial transporters (Foltyn et al. 2005; Martineau et al. 2006). Agents targeting such proteins may prove to be an effective method of increasing cerebral D-serine and occupancy of the NMDAR glycine site, which could overcome the difficulties D-serine and similar compounds have with penetrating the blood-brain barrier (Coyle and Tsai 2004; Bauer et al. 2005). Inhibiting DAO function in the brain is of particular interest as it would circumvent any nephrotoxicity associated with high levels of systemic D-serine (Maekawa et al. 2005a). DAO is a peroxisomal flavoprotein that at physiological pH is highly selective for D-serine, and in the brain, DAO is located predominantly in astrocytes (Mothet et al. 2000). An inverse correlation between the brain distribution of DAO and D-serine evinces the efficacy of this enzyme, with the most abundant DAO expression located in the D-serine-sparse hindbrain and cerebellum (Schell et al. 1995; Moreno et al. 1999). To study the effects of limiting DAO function, we tested a line of mice carrying a single point mutation (G181R) that results in a complete lack of DAO activity and consequently augmented D-serine in serum and brain (Sasaki et al. 1992; Hashimoto et al. 1993). These mice have previously been shown to exhibit an in vitro increase in NMDAR-mediated excitatory postsynaptic currents in dorsal horn neurons of the spinal cord and an in vivo elevation of cGMP that is indicative of augmented NMDAR activity (Wake et al. 2001; Almond et al. 2006). This demonstrates that reduced DAO function is capable of augmenting NMDAR activation, and it may follow that cognitive and extinction processes influenced by NMDARs are enhanced in Dao1G181R mutant mice. To investigate this possibility, we assessed the effects of the Dao1G181R mutation on learning, memory, and extinction in Morris water maze (MWM) and in contextual and cued fear conditioning paradigms.  相似文献   
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67.
Gender and Mathematical Problem Solving   总被引:1,自引:0,他引:1  
Duffy  Jim  Gunther  Georg  Walters  Lloyd 《Sex roles》1997,37(7-8):477-494
The relationship between gender and mathematical problem-solving among high ability students depends on the attributes of the problem solving questions. This was evident in the present study of 12-year-olds. The children were from predominately White families. Eighty-three males and 76 females were tested in both the fall and the spring on the Fennema-Sherman Mathematics Attitudes Scales and on the Canadian Test of Basic Skills (CTBS). In the Spring, students were also tested on the GAUSS. Both the CTBS and the GAUSS measure mathematical problem solving. Among high ability students, there were gender differences on the problem-solving scale of the CTBS but not on the GAUSS, even though the GAUSS was independently rated as the more abstract and difficult of the two tests. The present study describes the implications of this for the question of the origin of gender differences in mathematics, and also looked at the relationship between attitudes toward mathematics and mathematical problem-solving performance.  相似文献   
68.
Exploring self-forgiveness   总被引:1,自引:0,他引:1  
This article presents the results of a phenomenological study of the experience of self-forgiveness. On the basis of in-depth interviews with seven subjects, self-forgiveness is described not as an achievement but rather as a gift where one moves from estrangement and brokenness to a sense of at-homeness.This article is based in part on a paper presented at the Eighth International Human Science Research Conference at the University of Aarhus, Denmark, in August 1989. The authors thank their colleagues Carolyn Grissom and Jodi Kelly for their helpful suggestions.  相似文献   
69.
This study was designed to provide a basis to understand better antifeminine stereotyped attitudes that occur in association with a stimulus no more informative about a person than her first name. College students, mostly freshmen and sophomores, ascribed connotative meanings to common and uncommon masculine and feminine first names while imagining either real or ideal persons. The results from 48 subjects disclosed that the semantic dimension of potency (e.g., strength and bravery) is likely to be a fundamentally important connotation associated more with masculine names than with feminine names. Two findings very much supported this conclusion. Thus, the potency dimension was the only one of five dimensions of semantic meaning that: (a) yielded any masculine-feminine difference in the ideal condition, and (b) showed a disfavorable connotation for feminine names in comparison to masculine names in either the real or ideal condition.  相似文献   
70.
On standardized tests of mathematical problemsolving, the typical finding has been that women scorelower than men. Experiment 1 manipulated gender labeling(female character, male character, or gender neutral) within the problem question to seewhether this accounted for gender differences inmathematical problem solving. Sixty-four seventh andeighth graders were tested on modified versions of theCanadian Test of Basic Skills (CTBS) with the resultsshowing that although gender labeling affected studentsperformance, it did not account for gender differences.Experiment 2 manipulated both gender labeling and gender stereotype threat for 174 universitystudents writing modified versions of a modelStandardized Achievement Test (SAT). Again, genderlabeling within problem questions did not account forgender differences. However, women scored lower thanmen when they believed that the test had previouslyshown gender differences. There was no gender differencein the performance of the same women and men when they believed that the test was merelycomparing Canadian students with American students. Thissuggests that gender stereotype threat could be a keyfactor in explaining gender differences in mathematical problem solving.  相似文献   
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