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91.
Giovanni Aresi Dawn X. Henderson Niambi Francese Hall-Campbell Emma Jane Frances Ogley-Oliver 《World Futures: Journal of General Evolution》2017,73(7):473-490
Community psychologists address social inequalities and problems by employing ecological principles, multiple methodologies, and participatory approaches to empower individuals, organizations, and communities to organize action and systems change. This article aims to contribute to mixed methods literature by presenting three models of mixed methods participatory research across a variety of geographic and sociocultural contexts. The models outline participatory processes and points of qualitative and quantitative data integration. Challenges related to the interplay between participatory approaches and mixed methods studies as well as implications on social science research are discussed. 相似文献
92.
The same social comparison information may be expressed in different ways (e.g. ‘I am better than him’ versus ‘he is worse than me’). The results of four studies indicated that the way social comparison is expressed can affect an individual's satisfaction (i.e. ‘better’ versus ‘worse’). Specifically, in upward comparisons, the expression ‘I am worse than him’ makes individuals feel less satisfied than the expression ‘he is better than me’. In downward comparisons, those who use the expression ‘I am better than him’ are more satisfied than those who use the expression ‘he is worse than me’. The motivation of information processing acted as the mediator. 相似文献
93.
X. Xi;F. Yang;L. Chen;J. Lu;L. Wang; 《British journal of psychology (London, England : 1953)》2024,75(6):1486-1496
The quality of Moutai-flavour Baijiu is highly dependent on Moutai-flavour Daqu (MTDQ), which needs to be stored for 6 months before using. It brings abundant bacterium, which can metabolize various enzymes and favour compounds. But the reasonable storage time of MTDQ prepared in different seasons is still uncertain. To this end, the study revealed a detailed bacterial profile of storage MTDQ prepared in three different seasons (specifically, they were stored start from spring, summer and autumn) by using high-throughput sequencing approach (next generation sequencing). Results showed that major phyla of storage MTDQ were Firmicutes, Proteobacteria, Actinobacteria, Bacteroidetes and Fusobacteria. The advantages of Firmicutes were Thermoactinomyces and Bacillaceae. Significant differences in bacterial community structures of MTDQ from different seasons and storage time were observed. Compared with summer and autumn MTDQ, the decrease of Thermoactinomyces and increase of Desmospora in spring MTDQ were the main differences and bacterial community structures of summer and autumn MTDQ were more similar. The variation trends of the bacteria community indicated that the effective time of storage period was appropriately 6 months for spring MTDQ, 2 months for summer MTDQ and more than 6 months for autumn MTDQ. These results showed that the length of storage time was associated with the season and it is reasonable to adjust the storage time of MTDQ with the season. 相似文献
94.
Armando X. Estrada Tahira M. Probst Jeremiah Brown Maja Graso 《Military psychology》2013,25(2):220-236
We use classical test theory (CTT) and item response theory (IRT) methodologies to examine the psychometric and measurement properties of an instrument designed to assess sexual orientation harassment among military personnel (N?=?71,989). CTT analyses indicated that items were unidimensional and exhibited adequate levels of reliability. IRT analyses demonstrated that the items functioned similarly and exhibited appropriate levels of item discrimination. However, the analyses also suggested that the sensitivity of the items may be limited. Differential test functioning analyses provided evidence of the measurement equivalence of the instrument across male and female respondents. The findings provide support for the psychometric properties and measurement equivalence of the instrument for measuring sexual orientation harassment among male and female military personnel. We discuss the implications of our findings for future research on sexual orientation harassment in the workplace. 相似文献
95.
The microstructure and crystallization behaviour of melt-spun Al88Ni9Ce2Fe1 amorphous alloy and nanophase composites have been studied by means of X-ray diffraction, transmission electron microscopy and scanning and isothermal calorimetry. The diffraction patterns from Al88Ni9Ce2Fe1 amorphous alloys are diffuse, indicating a basically amorphous structure but contain two rings presumed to be associated with quenched-in nuclei. In the cases of Al88Ni9Ce2Fe1 nanophase composites, nanoscale precipitated particles are homogeneously dispersed in an amorphous matrix, and the crystallite diameter and volume fraction are sensitive to quenching conditions. During thermal crystallization, a two-step phase transformation occurs in the amorphous alloy and nanocomposites, which is characterized by a diffusion-controlled precipitation of nanoscale Al particles and the growth of a Al3(Ni, Fe) nanophase prior to a Al11Ce3 nanophase. This study gives insight into structure-control for obtaining nanophases dispersed in an amorphous matrix by rapid quenching. 相似文献
96.
Magnesium oxide (MgO) films and particles have been collected by pressurised filtration of a Mg-8.6wt%Al-0.67wt%Zn (AZ91D) alloy melt. The morphology of the oxides and their interfaces with the α-Mg phase were investigated by high-resolution transmission electron microscopy. It was found that the oxide films consisted of large numbers of sub-micrometre-sized MgO particles, and that melt shearing can effectively break up the oxide films and disperse the oxide particles. For the first time, orientation relationships (ORs) of OR I: [1?1?1]MgO～2° from (0?0?0?1)α-Mg and (0?1?1)MgO?//[2?1?1?0)α-Mg; and OR II: (1?1?1)MgO//(1?1?0?1)α-Mg and [0?1?1]MgO//[1?2?1?1]α-Mg, were observed between the MgO particles and the α-Mg matrix. The calculated Bramfitt planar disregistries were 5.5% and 2.5% for the two ORs, respectively, indicating good lattice matching between MgO and α-Mg at the interface. With the evidence of grain refinement effect observed in the sheared AZ91D magnesium alloy, the possibility of MgO particles to act as potent nucleants for heterogeneous nucleation of α-Mg grains is discussed in terms of the crystallographic criterion. 相似文献
97.
J. Cormier M. Jouiad F. Hamon P. Villechaise X. Milhet 《Philosophical Magazine Letters》2013,93(8):611-620
Very high temperature thermal cycling has been performed on the single crystal superalloy MC2 to evaluate the effect of periodic overheating on creep behavior. The experiments consist of alternately performing 1 min dwell time at 1100°C and 1150°C for every 15 min during creep test at 1050°C/120 MPa. Both thermal cycling and prior γ′-rafting appear to be deleterious to the cyclic creep properties. The observed non-isothermal creep behavior is correlated with γ′-dissolution/coalescence processes, especially during overheatings where γ′ micro-rafts seem to play a significant role. 相似文献
98.
X. Zhang 《Philosophical Magazine Letters》2013,93(1):55-65
A continuum model is proposed to address the effects of deformation twinning on ductile versus brittle fracture behaviour of low strain-hardening fcc metals after exhaustion of work hardening. Instead of discrete twin nucleation, a number of partial dislocations ahead of the tip exhibit themselves as twins at the final stage of failure. The crack-tip plasticity is amended for deformation twinning and the constitutive form for the flow strength of arrays of twins of the same sign is expressed as a second gradient of microrotation for their coupling. The twins not only shield the crack tip but also inhibit further dislocation emission to form a dislocation-free zone (DFZ) in the immediate vicinity of the tip. The stress fields induced by deformation twinning lead to fracture branching under Mode I loading. The model is borrowed from the conceptual model presented by Beltz et al. [Acta Mater. 44 3943 (1996)], based on the equivalence of the stresses derived from twin-based crack-tip plasticity, macroscopic plasticity and elasticity on the DFZ boundary. The DFZ size and the crack-tip shielding ratio are obtained, as well as the branching angle. The branching angle is noteworthy for low strain-hardening metals. A strong dependence of the toughness on intrinsic surface energy and hardening index is examined. The toughness reduction due to crack-tip constraints and in the ductile-to-brittle transition (DBT) temperature region is revisited and found to be in agreement with experimental observations and available predictions. 相似文献
99.
Electropulsing usually promotes a metastable phase to evolve towards its equilibrium state. This work reports an alternative case, where electropulsing promotes the decomposition of the stable δ-phase in duplex stainless steel at high temperature. This decomposition enables both the γ-phase and the σ-phase in the steel to survive and hence to strengthen it at high temperature. The hardness of the quenched sample with electropulsing treatment is 49.4% higher than that without electropulsing treatment. A fundamental understanding of the observation is developed. 相似文献
100.
We investigated how situational (gain–loss), informational (opportunity–threat framing) and dispositional (achievement motive and avoidance motive) variables affected opportunity–threat perception and risky choice in managerial decision-making contexts. In Study 1, the risk preference of the participants showed a reflection effect due to situational differences (gain or loss) and a partial framing effect caused by presenting the same choice information in terms of either opportunities or threats. However, both effects were in the opposite direction of predictions from prospect theory. Gains and positive framing enhanced risk-seeking preference whereas losses and negative framing augmented risk-averse preference. Risk-seeking choices were mediated by opportunity perception whereas risk-averse choices were mediated by threat perception. In Study 2, the participants high in achievement motive perceived greater opportunities in a negative situation, and the participants high in avoidance motive perceived greater threats in a positive situation, suggesting that ambition (achievement motive) operates more significantly in the face of adversities whereas cautiousness (avoidance motive) functions more significantly in prosperity. 相似文献