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81.
The present study provides evidence for the role of ferrite-grain-size distributions on the occurrence of void initiation in a low-carbon steel. Various thermomechanical treatments were undertaken to create ultrafine, bimodal and coarse distributions of ferrite grain sizes. A two-parameter characterisation of probable void initiation sites is proposed, namely an elastic modulus difference and a difference in Schmid factor of the grains surrounding the void. All microstructures were categorised based on the ability to facilitate or resist void nucleation. For coarse grains, the elastic modulus and the Schmid factor differences are the highest, while they are intermediate for ultrafine grains and the lowest for the bimodal microstructure.  相似文献   
82.
ABSTRACT

We present results for the structural, electronic, vibrational, and electron-phonon coupling properties of LaSn3 and CaSn3 adopting the simple cubic AuCu3-type structure obtained using the the generalised gradient approximation of the density functional theory and plane wave ab initio pseudopotential method. Our electronic results show that both materials display metallic character with several bands, which have mainly Sn 5p character, crossing the Fermi level. The calculated phonon spectrum of LaSn3 accords very well with reported experimental measurements. The weights of the peaks in the Eliashberg spectral function of both compounds are enhanced with the use of experimental lattice constant in our electron-phonon calculation, increasing the value of average electron phonon coupling parameter from 0.876 to 0.937 for LaSn3 (by 7%) and from 0.642 to 0.725 for CaSn3 (by 13%). The use of experimental lattice constant also improves the agreement between theoretical and experimental values of the superconducting temperature for both compounds.  相似文献   
83.
The structural validity of the Personal Globe Inventory (PGI, Tracey, 2002) as applied to a Caribbean sample of university students in Jamaica (N = 103) and Trinidad (N = 118) was examined. The fit of the data to Holland's six-type RIASEC, the PGI eight-type model, and the PGI spherical structure was examined using the randomized test of hypothesized order relations. The results demonstrated that the circular structure (i.e. RIASEC and the eight-type model), unlike the spherical structure, fits the Caribbean data well. No structural differences were found between gender and nationality. Further examination of the cultural perception of prestige in a Caribbean sample is warranted. Overall, the results support the structural validity of the PGI in Caribbean applications.  相似文献   
84.
This study explored the factor structure of the Proactive Coping Inventory (PCI) to determine whether its six-factor structure holds within the Southern African context. Data on proactive coping were collected from students attending three universities, one each in Botswana (n=88, females=45.5%, mean age=21.31 years, SD=2.04), Namibia (n=38, females=47.4%, mean age=24.21 years, SD=3.47) and South Africa (n=496, females=56.9%; mean age=22.27 years, SD=2.60). Exploratory factor analysis was used to determine the factor structure of the PCI. Findings suggest that the PCI is comprised of two factors: Future-Oriented Coping (comprised of Proactive Coping, Reflective Coping, Strategic Planning and Preventive Coping) and Support Seeking (comprised of Instrumental Support Seeking and Emotional Support Seeking). This is in line with theory that suggests that individuals cope by means of persisting towards goal attainment.  相似文献   
85.
This article examines some of the story conventions of network television news to explain the ways in which healthcare interest groups develop and maintain their presence in this medium—a process that has significant implications for public understanding of healthcare issues, and therefore to bioethics. The article is divided into three sections. The first section focuses on three major normative conventions of television news: adherence to a simple narrative structure, the balance ethic, and avoidance of the “think-piece” and outlines the basic strategies available to interest groups for exploiting these normative conventions. Section two introduces three case studies of organizations and individuals who have run high-profile media campaigns. Section three explores the implications for bioethics of the observations made in this article.  相似文献   
86.
According to the “story model” a juror constructs an implicit mental model of a story telling what happened as the basis for the verdict choice. But the explicit justification of a verdict choice could take the form of a story (knowledge telling) or the form of a relational (knowledge-transforming) argument structure that brings together diverse, non-chronologically related pieces of evidence. The study investigates whether people tend towards knowledge telling or knowledge transforming, and whether use of these argument structure types are related to skilled argument and epistemic understanding. A sample of people on jury duty chose and justified verdicts in two abridged cases. Participants tended to display the same argument structure and argument skill across cases. Those using knowledge-transforming structures were more successful at the juror argument skills task and had a higher level of epistemic understanding. The discussion suggests that jurors approach their task with an epistemic orientation towards knowledge telling or knowledge transforming.  相似文献   
87.
ABSTRACT

Two experiments were conducted to examine possible sources of age-related decline in sequential performance: age differences in sequence representation, retrieval of sequence elements, and efficiency of inhibitory processes. Healthy young and older participants learned a sequence of eight animal drawings in fixed order, then monitored for these targets within trials of mis-ordered stimuli, responding only when targets were shown in the correct order. Responses were slower for odd numbered targets, suggesting that participants spontaneously organized the sequence in two-element chunks. Perseverations (responses to previously relevant targets) served as an index of inhibitory inefficiency. Efficiency of chunk retrieval and self-inhibition were lower for older than for younger adults. Increasing environmental support in Experiment 2 through overt articulation of current chunk elements showed a pattern of results similar to Experiment 1, with particular benefit for older adults. The findings suggest an underlying susceptibility to interference in old age.  相似文献   
88.
There have been a small number of investigations of alexithymia in multiple sclerosis (MS) using the 20-item Toronto Alexithymia Scale (TAS-20). However, the TAS-20 factor structure has not yet been evaluated in a MS patient sample, and earlier Spanish translations of this instrument require some improvement. We aimed to evaluate the factorial validity and reliability of an improved Spanish translation of the TAS-20 (the TAS-20-S). The TAS-20-S was completed by 221 MS patients. Confirmatory factor analysis was used to compare the fit of six different factor models. Internal consistency and retest reliability coefficients were also computed. The correlated three-factor model and the higher-order factor model made up of Difficulty Identifying Feelings, Difficulty Describing Feelings, and Externally Oriented Thinking achieved the best fit. Alpha coefficients ranged between .87 and .67; mean inter-item correlations ranged between .48 and .20; and retest correlations after 6 months ranged between .61 and .52. A high degree of alexithymia was present in 18.1% of the sample. Reliability and the traditional three-factor structure were demonstrated for the TAS-20-S, which can now be recommended for assessing an aspect of emotional processing in MS patients.  相似文献   
89.
In English, new information typically appears late in the sentence, as does primary accent. Because of this tendency, perceivers might expect the final constituent or constituents of a sentence to contain informational focus. This expectation should in turn affect how they comprehend focus-sensitive constructions such as ellipsis sentences. Results from four experiments on sluicing sentences (e.g., The mobster implicated the thug, but we can't find out who else) suggest that perceivers do prefer to place focus late in the sentence, though that preference can be mitigated by prosodic information (pitch accents, Experiment 2) or syntactic information (clefted sentences, Experiment 3) indicating that focus is located elsewhere. Furthermore, it is not necessarily the direct object, but the informationally focused constituent that is the preferred antecedent (Experiment 4). Expectations regarding the information structure of a sentence, which are only partly cancellable by means of overt focus markers, may explain persistent biases in ellipsis resolution.  相似文献   
90.
Three experiments are reported that studied the priming of word order in German. Experiment 1 demonstrated priming of the order of case-marked verb arguments. However, order of noun phrases and order of thematic roles were confounded. In Experiment 2, we therefore aimed at disentangling the impact of these two possible factors. By using primes that differed from targets in phrase structure but were parallel with regard to the order of thematic roles, we nevertheless found priming demonstrating the critical impact of thematic roles. Experiment 3 replicated the priming effects from Experiments 1 and 2 within participants and revealed no evidence for a modulation of priming by phrase structure. Consequently, our findings suggest that word order priming crucially depends on the structural outline of thematic roles rather than on the linearization of phrases.  相似文献   
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