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11.
Nanocrystalline nickel titanate (NiTiO3) composite powders were prepared by the sol–gel process combined with a surfactant-assisted template method. The resulting powders were calcined at different temperatures ranging from 150°C to 750°C for 2 h in air. The results revealed that a pure hexagonal phase of NiTiO3 could be obtained at the low temperature of 750°C. The phase evolution of NiTiO3 was investigated by X-ray diffraction patterns, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Particle size and morphology were studied by transmission electron microscopy.  相似文献   
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In dynamic task environments, decision makers are vulnerable to two types of errors: sticking too closely to the rules (excessive conformity) or straying too far from them (excessive deviation). We explore the effects of process and outcome accountability on the susceptibility to these errors. Using a multiple‐cue probability‐learning task, we show that process accountability encourages conformity errors and outcome accountability promotes deviation errors. Two additional studies explore the moderating effects of self‐focused and other‐focused group norms. Self‐focused norms reduce the effect of process accountability on excessive conformity. Other‐focused norms reduce the effect of outcome accountability on excessive deviation. Our results qualify prevailing claims about the benefits of process over outcome accountability and show that those benefits hinge on prevailing group norms, on the effectiveness of prescribed decision rules, and on the amount of irreducible uncertainty in the prediction task. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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This study developed an HIV risk reduction intervention for people living with HIV (PLWH) obtaining care at primary healthcare clinics in KwaZulu-Natal, South Africa by (1) conducting elicitation research to understand the dynamics of risk behaviour among PLWH, (2) modifying an existing HIV risk reduction intervention based on research findings and (3) conducting a pilot study to evaluate feasibility, acceptability and fidelity of the modified intervention implemented by trained lay counsellors at a rural clinic in KwaZulu-Natal. A total of 61 healthcare providers and 77 HIV+ patients from four primary healthcare clinics participated in 14 focus groups and 20 individual interviews to identify informational, motivational and behavioural skills (IMB) factors contributing to PLWH's sexual risk behaviour. Elicitation research findings were incorporated into a revised version of Options for Health, an evidence-based risk reduction intervention for PLWH in clinical care. In a 5-day training, lay counsellors learned strategies to address IMB barriers to safer sex identified in elicitation research. The revised intervention, which was implemented by six counsellors with 39 patients, was feasible to implement, acceptable to patients and counsellors, and implemented with good fidelity. This study makes an important contribution towards development of a theory-based HIV risk reduction intervention for PLWH linking prevention with treatment in South Africa.  相似文献   
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Computational modeling assists in analyzing the specific functional role of the cellular effects of acetylcholine within cortical structures. In particular, acetylcholine may regulate the dynamics of encoding and retrieval of information by regulating the magnitude of synaptic transmission at excitatory recurrent connections. Many abstract models of associative memory function ignore the influence of changes in synaptic strength during the storage process and apply the effect of these changes only during a so-called recall-phase. Efforts to ensure stable activity with more realistic, continuous updating of the synaptic strength during the storage process have shown that the memory capacity of a realistic cortical network can be greatly enhanced if cholinergic modulation blocks transmission at synaptic connections of the association fibers during the learning process. We here present experimental data from an olfactory cortex brain slice preparation showing that previously potentiated fibers show significantly greater suppression (presynaptic inhibition) by the cholinergic agonist carbachol than unpotentiated fibers. We conclude that low suppression of non-potentiated fibers during the learning process ensures the formation of self-organized representations in the neural network while the higher suppression of previously potentiated fibers minimizes interference between overlapping patterns. We show in a computational model of olfactory cortex, that, together, these two phenomena reduce the overlap between patterns that are stored within the same neural network structure. These results further demonstrate the contribution of acetylcholine to mechanisms of cortical plasticity. The results are consistent with the extensive evidence supporting a role for acetylcholine in encoding of new memories and enhancement of response to salient sensory stimuli.  相似文献   
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Researchers in the field of conjoint analysis know the index-of-fit values worsen as the judgmental error of evaluation increases. This simulation study provides guidelines on the goodness of fit based on distribution of index-of-fit for different conjoint analysis designs. The study design included the following factors: number of profiles, number of attributes, algorithm used and judgmental model used. Critical values are provided for deciding the statistical significance of conjoint analysis results. Using these cumulative distributions, the power of the test used to reject the null hypothesis of random ranking is calculated. The test is found to be quite powerful except for the case of very small residual degrees of freedom.The authors thank the editor, the three reviewers and Ellen Foxman for helpful comments on the paper. Sanjay Mishra was a doctoral student at Washington State University at the time this research was completed. He is currently in the Department of Marketing at the University of Kansas.  相似文献   
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To identify aspects of parental burden associated with borderline personality disorder (BPD), an anonymous internet survey linked to BPD support websites was developed for parents to complete on their BPD offspring and unaffected siblings. The questions cover aspects of the child's life from pregnancy through young adulthood, and query about the impact of the child's BPD on six domains of the parent's life, including physical and emotional health, marriage, job, standard of living, social life, and career trajectory. Additionally, financial burden was assessed with questions pertaining to insurance and out-of pocket costs associated with the BPD disorder. BPD offspring were identified by meeting diagnostic criteria embedded within the survey and having been given a diagnosis of BPD by a professional at some point in their life. We report on 233 female offspring meeting strict criteria for BPD. Parents of daughters with BPD endorsed varying levels of impact on the six domains comprising burden with the largest impact on emotional health which was impacted in over 88% of the respondents. Over 50% of parents endorsed four or greater of the six burden items. Particular aspects of the offspring's BPD symptom profile correlated with intensity of parental burden included including problems in adolescence with acting out behavior (p < .000), property destruction (.003), delusional symptoms (.007), and hallucinatory symptoms (.008). A subgroup of respondents provided data on specific financial expenses. The average and median out-of-pocket expense was $60,087, and $10,000. Insurance costs totaled an average of $108,251 with a mean of $20,000. The average cost per year after diagnosis was $14,606 out-of-pocket and $45,573 billed to insurance. The median cost per year after diagnosis was $3,667 out-of-pocket, and $12,500 billed to insurance. After adjusting for household income, a female proband who had been raped incurred roughly $40,000 more in BPD-related costs, while a diagnosis of conduct disorder led to about $50,000 in additional costs. Parents of female offspring with BPD experience burden in multiple domains of their life and many have incurred substantial financial expense. Increasing awareness of co-morbid conditions in the BPD proband that significantly increase parental burden may be indicators for the provision of increased family support.  相似文献   
17.
Although response interruption and redirection (RIRD) and multiple schedule arrangements have sometimes been shown to be effective in reducing stereotypy for individuals with autism spectrum disorder (ASD), important questions remain about optimal methods for facilitating generalization and social validity. In the current study, we sought to extend the literature on stereotypy treatment and MSAs in several ways. First, we programmed for generalization by conducting sessions with two exemplars of two different categories of activities (i.e., school work, toy play) and assessing generalization with novel exemplars and activities and during the participant's typical instructional program. Second, we used RIRD instructions that were contextual models of appropriate behavior relevant to each activity. Third, during the free access component of the multiple schedule, we used a child's play tent as a first step toward teaching participants to engage in stereotypy during private free time. For all three participants with ASD, stereotypy decreased quickly and substantially, with reductions generalizing to novel activities and contexts. An extensive social validity assessment with board-certified behavior analysts indicated high social acceptability of the goals, procedures, and outcomes.  相似文献   
18.
This research evaluates the stability of time usage relationships among discretionary activities. Traditional economists view products or services as substitutes if both can satisfy the same need of the consumer; they are complements if they are consumed jointly in order to satisfy some particular need. Complementary activities are grouped together in activity sets defined on an a priori basis. Several research questions are developed to investigate the following issues: (a) the stability over time of overall relationships between activities, in terms of visual representation using multidimensional scaling maps, and (b) the validity and stability of a priori classification of activities in activity sets. The results from multidimensional scaling maps are validated using structural equation modeling. The results suggest that time usage relationships are temporally stable. The broad needs of respondents, as represented by interrelationships between activities in sets, were found to be stable. We present reasons for believing that the conclusions of stability are comprehensive and can be used in the real‐world.  相似文献   
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