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1.
In this study, we report on the influence of high pressure on the microstructure evolution of cryomilled nanostructured Al alloy powders during spark plasma sintering (SPS). Our experimental results suggest that the particular mechanism that governs grain growth during SPS depends on the magnitude of the applied pressure. In the case of material consolidated at a high pressure (e.g. 500 MPa), grain coarsening occurs via a combination of thermally activated grain boundary (GB) migration, stress-coupled GB migration and grain rotation-induced grain coalescence. In contrast, in the case of the material consolidated at a low pressure (50 MPa), grain growth occurs primarily via thermally activated GB migration.  相似文献   

2.
The purpose of this study was to examine developmental change and the influence of shyness on social problem-solving (SPS). At 24, 36, and 48 months, children (N = 570) were observed while interacting with an unfamiliar peer during an SPS task and at 24 months, maternal report of shyness was collected. Results showed that across the full sample, children displayed low but stable levels of withdrawn SPS and increasing levels of SPS competence over development. In addition, results showed multiple trajectories of withdrawn and competent SPS. Shyness was associated with high-increasing and high-decreasing withdrawn SPS trajectories compared with the low-increasing withdrawn SPS trajectory. Shyness was also associated with the low-increasing compared with the high-increasing SPS competence trajectory. Findings demonstrate the development of SPS competence over early childhood, and the influence of early shyness on this developmental course, with some shy children showing improvement in SPS skills and others continuing to show SPS difficulties over time.  相似文献   

3.
The significance of the English past tense in current cognitive science is that it offers a clear contrast between a potentially rule-based system-the procedures for forming the regular past tense-and an unpredictable and idiosyncratic set of irregular forms. This contrast has become a focus for a wide-ranging debate about whether mental computation requires the use of symbols. Highly regular combinatorial phenomena, such as the regular past tense, are prime candidates for rule-based symbolic computation. Earlier research concentrated on the evidence for this during language acquisition, looking at how children learned the English regular and irregular verb systems. Over the last five years attention has shifted towards the properties of the adult system, and we review here some recent research into the neural correlates of the two types of procedure. The evidence suggests that there are divergences in the neural systems underlying the generation and perception of regular and irregular forms. Regular inflected forms seem to involve primarily combinatorial processes, while irregular forms appear to have a hybrid status, sharing their semantic properties with the regular forms but diverging in the phonological domain, where their form representations are stored as complete units. This indicates that the regular and irregular past tenses may not, after all, provide a clean contrast in the types of mental computation they implicate.  相似文献   

4.
Spatial pattern separation (SPS) and spatial pattern completion (SPC) have played an increasingly important role in computational and rodent literatures as processes underlying associative memory. SPS and SPC are complementary processes, allowing the formation of unique representations and the reconstruction of complete spatial environments based on partial spatial information. We present two novel computerized navigational tasks as human analogs of well-established rat SPS and SPC tasks. Results from these tasks show that human participants are sensitive to increasing SPS and SPC demands. Specifically, memory accuracy decreased with decreasing separation distance between target and foil locations in the SPS task and with decreasing number of distal spatial cues in the SPC task. These tasks set the stage for valuable future directions, including the use of these tasks with imaging and clinical populations.  相似文献   

5.
HIV medication adherence remains a challenge and limits the degree to which treatment benefit can be maximized. This study tested an explanatory model of HIV medication adherence using a social problem-solving (SPS) framework. Associations of SPS with adherence are hypothesized to be direct and/or indirect via psychological health. HIV+ adults were interviewed using validated measures of SPS, psychological health, and antiretroviral therapy (ART) medication adherence. Structural equation modeling (SEM) techniques were used to test hypothesized relationships and to evaluate overall fit of the model to the data. SEM supported an indirect association (but not direct) of SPS on adherence via psychological health among the 545 HIV+ adults included in the analyses. Overall, the findings resulted in a model of adherence that offered very good fit to the data and correctly classified 97% of the cases as adherent versus nonadherent. Results support the use of SPS as a conceptual framework for understanding adherence to ART. Findings offer rationale and direction for SPS interventions to enhance adherence by improving psychological health. Such approaches, if effective, have the potential to positively impact psychological well being and adherence, thereby maximizing clinical benefit from treatment, which is linked to lower mortality from AIDS.  相似文献   

6.
Abstract

This study examined the interplay between behavioral inhibition/activation systems (BIS/BAS) sensitivity, attachment insecurity (i.e., anxiety and avoidance), and Big Five personality traits in predicting sensory processing sensitivity (SPS). We have specifically tested three alternative theoretical models to explain the process through which BIS/BAS sensitivity link to SPS; unique effects of attachment dimensions and personality traits, as well as moderating and mediating role of these variables. Participants (N?=?494) completed the highly sensitive Person scale, BIS/BAS scales, experiences in close relationships-revised scale, and big five inventory. The findings revealed the complex role of attachment dimensions and personality traits on SPS. Attachment avoidance, but not attachment anxiety, moderated the effect of BIS activity on SPS indicating that, compared to those with high BIS sensitivity, those with low levels of both BIS and attachment avoidance reported lower level of SPS. Attachment anxiety, neuroticism, extraversion, and openness partially mediated the effects of BIS on SPS. Conceptual implications of the findings and suggestions for future research are discussed.  相似文献   

7.
Sensations and thoughts have been described as potentially related to self-awareness. We therefore asked whether sensations that arise in the absence of external triggers, i.e., spontaneous sensations (SPS), which were shown to relate to interoception and perception of the self, vary as a function of the individual propensity to generate spontaneous thoughts, i.e., mind-wandering. The Mind Wandering Questionnaire (MWQ) was used as a specific tool to assess the frequency and propensity to mind-wander several weeks before completing an SPS task. Correlational analyses between the MWQ score and SPS showed that greater propensity to mind-wander coincided with widespread perception of SPS, while lesser propensity to mind-wander coincided with more spatially restricted perception of SPS. The results are interpreted in light of the role of spontaneous thoughts and sensations in self-awareness. The potential psychological processes and the way they might regulate the relation between mind-wandering and the perception of SPS are discussed.  相似文献   

8.
Perceived social support is a multifaceted construct conceptualized as one's cognitive appraisal as to the existence of a connection to others, based on trust, on whom one can rely on when necessary. The aim of this paper is to examine the psychometric properties of perceived social support, using the following scales: Social Support Questionnaire-Short Form (SSQ6) and Social Provisions Scale (SPS), on a sample of 855 first year university students – 575 females and 280 males – enrolled in 16 professional degrees at the University of Santiago de Compostela (Spain). The SSQ6 Scale assesses the dimensions of perceived support availability and satisfaction, whilst the SPS Scale assesses its social support functions. The factor analysis conducted confirms the SSQ6 Scale's two-dimensional model and the SPS Scale's six-factor structure. Internal consistency of both scales is satisfactory, as is the evidence of validity obtained from the correlations between the two scales and their subscales. The results reveal that the Spanish version of the SSQ6 and SPS scales are reliable and valid measurements for assessing perceived social support amongst university students.  相似文献   

9.
Taatgen NA  Anderson JR 《Cognition》2002,86(2):123-155
Learning the English past tense is characterized by a U-shaped learning function for the irregular verbs. Existing cognitive models often rely on a sudden increase in vocabulary, a high token-frequency of regular verbs, and complicated schemes of feedback in order to model this phenomenon. All these assumptions are at odds with empirical data. In this paper a hybrid ACT-R model is presented that shows U-shaped learning without direct feedback, changes in vocabulary, or unrealistically high rates of regular verbs. The model is capable of learning the default rule, even if regular forms are infrequent. It can also help explore the question of why there is a distinction between regular and irregular verbs in the first place, by examining the costs and benefits of both types of verbs.  相似文献   

10.
Stiff-person syndrome (SPS) is a rare disease of severe progressive muscle stiffness in the spine and lower extremities with superimposed muscle spasms triggered by external stimuli. Patients with SPS are often referred for psychiatric evaluation and the psychiatrist may be the first to diagnosis SPS. Psychosocial stressors often precede the first manifestations of the disease; depression, anxiety, and alcohol abuse are comorbid illnesses. The identification of an association with antibodies to glutamic acid decarboxylase (GAD) was invaluable for definitively establishing a pathological basis for the disease; antibodies to amphiphysin and gephyrin are also found in cases of SPS but at much lower frequencies. Whether the antibodies inhibit GAD activity in vivo, target GAD-expressing neurons for immune-mediated destruction, are part of a wider immune process, or are merely a marker for destruction of GAD-expressing neurons by an independent neurodegenerative process is not yet clear. Both electromyography and the detection of GAD antibodies are useful in establishing a diagnosis of SPS. Treatment of SPS includes the use of immunomodulating therapies (plasmapheresis and intravenous immunoglobulins) and symptomatic treatment with benzodiazepines and baclofen. The use of tricyclic antidepressants and rapid withdrawal from therapy should be avoided.  相似文献   

11.
Clinical research has linked post-traumatic stress disorder (PTSD) with deficits in fear extinction. However, it is not clear whether these deficits result from stress-related changes in the acquisition or retention of extinction or in the regulation of extinction memories by context, for example. In this study, we used the single prolonged stress (SPS) animal model of PTSD and fear conditioning procedures to examine the effects of prior traumatic stress on the acquisition, retention, and context-specificity of extinction. SPS administered one week prior to fear conditioning had no effect on the acquisition of fear conditioning or extinction but disrupted the retention of extinction memories for both contextual and cued fear. This SPS effect required a post-stress incubation period to manifest. The results demonstrate that SPS disrupts extinction retention, leading to enhanced fear renewal; further research is needed to identify the neurobiological processes through which SPS induces these effects.  相似文献   

12.
To evaluate the construct validity (convergent and divergent) of Sivik Psycho Somaticism test (SPS) and test of Operationality (OPER), Pearson correlation coefficients between SPS scales and subscales and Karolinska Scheme of Personality (KSP) were calculated. Seventy-eight healthy individuals and 196 psychosomatic patients completed the SPS and OPER tests and KSP. The results show that the SPS and OPER subscales are significantly correlated to most KSP subscales. The correlations were higher for the psychosomatic group than for the normal population. The results confirm the validity of the SPS and OPER constructs.  相似文献   

13.
This paper presents a further examination of the Social Psychopathy Scale (SPS) which was designed to measure psychopathic-like characteristics in normal samples; until the present study, data was only available for U.S. subjects. The SPS, Socialization Scale (SO) and the EPQ were administered to 92 U.K. subjects. The mean scores and factor structure of the SPS obtained in the present study were compared with those obtained in a previous study with U.S. subjects and revealed only a limited degree of correspondence. There was a predicted negative correlation between the SPS and SO and predicted positive correlation between the SPS and the P-scale of the EPQ. There was some variability in the relationship between the SO and subscales of the EPQ with the factors of the SPS obtained in the present study. Two aspects of the results are discussed: the variability in the factor structure of the SPS, and the nature of the concept of social psychopathy.  相似文献   

14.
Varying standards and quality among Norwegian school psychology services (SPS) have resulted in national SPS support and developmental programs. The present study aimed to reveal SPS quality dimensions to suggest a basis for development of service standards. Teachers (333) and administrators (136) responsible for corresponding cases referred to the SPS responded to a questionnaire including indices of case service quality and collaboration between schools and SPS. The statistical analyses included factor analyses and a multiple regression analysis. The data and results from an earlier study of parents' quality dimensions were included in an items analyses. The result suggests five central SPS quality dimensions: availability, participation, consideration, effectiveness and security. While effectiveness has the strongest effect on the evaluation of case service quality both for parents and school personnel, the dimensions have different significance for different consumer groups. Relations to general service quality dimensions and consequences of the findings are discussed.  相似文献   

15.
The study investigated whether the P600/SPS component is sensitive to the richness of semantic content in sentences. ERPs were recorded while 30 native Swedish speakers read sentences, of which half were syntactically correct and half contained a syntactic violation. Both kinds of sentences came in one of three types of descending semantic completeness: semantically coherent sentences, sentences which were incoherent due to violations of selectional restrictions, or sentences of pseudo words, hence void of lexical content. In the semantically coherent sentences a P600/SPS was found for the syntactic violation. A less salient positivity was found for the violation in the semantically incoherent sentences. No P600/SPS was found for the syntactic violation in the pseudo word sentences and no LAN component in any sentence type. The results are interpreted as supporting the hypothesis that the P600/SPS component reflects a semantically based reanalysis process.  相似文献   

16.
To evaluate the construct validity (convergent and divergent) of the Sivik Psycho Somaticism test (SPS) and test of Operationality (OPER), Pearson correlation coefficients between SPS scales and subscales, OPER and Minnesota Multiphasic Personality Inventory (MMPI) subscales Hypochondria (Hs), Depression (D), Hysteria (Hy) and Alexithymia (Al) were calculated. Eighty-eight healthy individuals and 285 psychosomatic patients completed the SPS and OPER tests and MMPI; Hs, D, Hy and Al. The results show that most of the SPS subscales and OPER are significantly correlated to several MMPI subscales in both a normal and a psychosomatic population. The results are in concordance with the theoretical hypotheses and confirm the validity of the SPS and OPER constructs.  相似文献   

17.
To evaluate the construct validity (convergent and divergent) of the Sivik Psycho Somaticism test (SPS) and test of Operationality (OPER), Pearson correlation coefficients between SPS scales and subscales, OPER and Minnesota Multiphasic Personality Inventory (MMPI) subscales Hypochondria (Hs), Depression (D), Hysteria (Hy) and Alexithymia (Al) were calculated. Eighty-eight healthy individuals and 285 psychosomatic patients completed the SPS and OPER tests and MMPI; Hs, D, Hy and Al. The results show that most of the SPS subscales and OPER are significantly correlated to several MMPI subscales in both a normal and a psychosomatic population. The results are in concordance with the theoretical hypotheses and confirm the validity of the SPS and OPER constructs.  相似文献   

18.
To evaluate the construct validity (convergent and divergent) of Sivik Psycho Somaticism test (SPS) and test of Operationality (OPER), Pearson correlation coefficients between SPS scales and subscales and Karolinska Scheme of Personality (KSP) were calculated. Seventy-eight healthy individuals and 196 psychosomatic patients completed the SPS and OPER tests and KSP. The results show that the SPS and OPER subscales are significantly correlated to most KSP subscales. The correlations were higher for the psychosomatic group than for the normal population. The results confirm the validity of the SPS and OPER constructs.  相似文献   

19.
The present investigations examined the factor structure and psychometric properties of two new self-report measures of social phobia, the Social Interaction Anxiety Scale (SIAS) and the Social Phobia Scale (SPS). A confirmatory factor analysis in Study I provided support for the fit of a two-factor model of the SIAS and SPS. Internal consistency estimates were high for the original two scales with a sample of 200 undergraduates. Also, using an item parceling procedure, the obtained internal consistency reliability indices for each parcel were acceptable. Results of the CFA in Study II provided support for the factorial stability of the model identified in Study I. Furthermore, multisample analyses showed invariant patterns for factor loadings and factor correlations across 138 men and 272 women. Gender differences were not observed in the mean SIAS and SPS scale and item scores. Both scales correlated negatively and significantly with measures of social desirability. Concurrent validity was established for the scales. The SPS was less specific than the SIAS to symptoms of social phobia.  相似文献   

20.
School-based, social problem-solving (SPS) training with children offers promise both for the prevention and remediation of social maladjustment. This article describes the SPS approach and offers rationales for its integration into the school curriculum. Illustrative SPS programs are next reviewed and compared in terms of relative strengths and application potential. Practical guidelines are offered for conducting of effective SPS interventions jointly by school mental health and teaching staffs. The article concludes with a brief consideration of future applied SPS research directions.  相似文献   

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