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971.
Daniel L. Fuller Nancy C. Gyurcsik Kevin S. Spink Lawrence R. Brawley 《Journal of applied social psychology》2012,42(12):2917-2932
Walking for transportation is associated with health benefits. Minimal theory‐based research has examined social cognitive and environmental predictors. This study examined social cognitions (self‐regulatory efficacy to plan/schedule and overcome barriers; distance and travel time cognitions) and an environmental factor (proximity) as predictors of walking for transportation. Participants (n = 105) were university students, faculty, and staff, living within a walkable distance to campus. Social cognitions and proximity measures were completed at baseline, followed by walking for transportation to/from the campus over 2 weeks. A hierarchical multiple regression analysis predicted walking (R2adjusted = .55; p < .05). Self‐regulatory efficacy to plan/schedule and overcome barriers were independent predictors (p's < .01). Findings supported theoretical contentions that self‐regulatory efficacy predicts walking for transportation. 相似文献
972.
Daniel C. Molden 《Social and Personality Psychology Compass》2012,6(2):156-169
Beyond motivations to achieve particular outcomes, people also have motivations to use particular strategies while pursuing these outcomes. This article integrates research on the latter strategic preferences and discusses the place of such research in the broader investigation of motivated thinking. A review of studies examining the strategic preferences stemming from both motivations for promotion versus prevention ( Higgins, 1997 ) and motivations for locomotion versus assessment ( Higgins, Kruglanski, & Pierro, 2003 ) illustrates that these preferences have unique effects on basic processes of judgment, including the evaluation of alternative hypotheses or counterfactuals, the prioritization of fast versus accurate information processing, and the recall and activation of knowledge from memory. Moreover, this review also demonstrates important interactions between strategic preferences and outcome preferences. Strategic preferences thus appear to make distinct and important contributions to understanding how motivation influences judgment and should feature prominently in general analyses of motivated thinking. 相似文献
973.
Tripping and falling is a serious health problem for older citizens due to the high medical costs incurred and the high mortality rates precipitated mostly by hip fractures that do not heal well. Current falls prevention technology encompasses a broad range of interventions; both passive (e.g., safer environments, hip protectors) and active (e.g., sensor-based fall detectors) which attempt to reduce the effects of tripping and falling. However the majority of these interventions minimizes the impact of falls and do not directly reduce the risk of falling. This paper investigates the prediction of gait parameters related to foot-to-ground clearance height during the leg swing phase which have been physically associated with tripping and falling risk in the elderly. The objective is to predict parameters of foot trajectory several walking cycles in advance so that anticipated low foot clearance could be addressed early with more volitional countermeasures, e.g., slowing down or stopping. In this primer study, foot kinematics was recorded with a highly accurate motion capture system for 10 healthy adults (25-32 years) and 11 older adults (65-82 years) with a history of falls who each performed treadmill walking for at least 10 min. Vertical foot displacement during the swing phase has three characteristic inflection points and we used these peak values and their normalized time as the target prediction values. These target variables were paired with features extracted from the corresponding foot acceleration signal (obtained through double differentiation). A generalized regression neural network (GRNN) was used to independently predict the gait variables over a prediction horizon (number of gait cycles ahead) of 1-10 gait cycles. It was found that the GRNN attained 0.32-1.10 cm prediction errors in the peak variables and 2-8% errors in the prediction of normalized peak times, with slightly better accuracies in the healthy group compared to elderly fallers. Prediction accuracy decreased linearly (best fit) at a slow rate with increasing prediction horizon ranging from 0.03 to 0.11 cm per step for peak displacement variables and 0.34 × 10(-3) - 1.81 × 10(-3)% per step for normalized peak time variables. Further time series analysis of the target gait variable revealed high autocorrelations in the faller group indicating the presence of cyclic patterns in elderly walking strategies compared to almost random walking patterns in the healthy group. The results are promising because the technique can be extended to portable sensor-based devices which measure foot accelerations to predict the onset of risky foot clearance, thus leading to a more effective falls prevention technology. 相似文献
974.
Y. Wang S.L. Shang H. Zhang L.-Q. Chen Z.-K. Liu 《Philosophical Magazine Letters》2013,93(12):851-859
To understand the Invar anomalies, such as negative thermal expansion and spontaneous magnetization, we have applied our recently developed thermodynamic framework for a system with itinerant-electron magnetism to the ordered Fe3Pt. The framework has coherently predicted the finite temperature intermixing between the fully ferromagnetic (FM) configuration and the spin-flipping configurations (SFCs). We have also discovered a tri-critical point at which a high-temperature second-order phase transition, between the fully ordered FM phase and the paramagnetic phase which is disordered due to SFCs, becomes first order at low temperatures. 相似文献
975.
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
976.
977.
Kathleen B. McDermott Jeffrey G. Ojemann Steven E. Petersen John M. Ollinger Abraham Z. Snyder Erbil Akbudak 《Memory (Hove, England)》2013,21(5-6):661-680
Functional magnetic resonance imaging (fMRI) was used to compare directly episodic encoding and retrieval. During encoding, subjects studied visually presented words and reported via keypress whether each word represented a pleasant or unpleasant concept (intentional, deep encoding). During the retrieval phase, subjects indicated (via keypress) whether visually presented words had previously been studied. No reliable differences were found during the recognition phase for words that had been previously studied and those that had not been studied. Areas preferentially active during encoding (relative to retrieval) included left superior frontal cortex, medial frontal cortex, left superior temporal cortex, posterior cingulate, left parahippocampal gyrus, and left inferior frontal gyrus. Regions more active in retrieval than encoding included bilateral inferior parietal cortex, bilateral precuneus, right frontal polar cortex, right dorsolateral prefrontal cortex, and right inferior frontal/insular cortex. 相似文献
978.
The present study used an informant method of psychiatric assessment to evaluate Saddam Hussein, and these results were compared to a posthumous assessment of Adolf Hitler. Eleven Iraqi adults who lived under Hussein's influence for a median of 24 years completed the Coolidge Axis II Inventory, a measure of 14 personality disorders. The mean consensus among the 11 raters was r = .57. It revealed that Hussein probably reached diagnostic threshold for the sadistic (T score M = 81.0), paranoid (T score M = 79.3), antisocial (T score M = 77.4), and narcissistic (T score M = 74.2) personality disorders. The correlation between the consensus profile for Hussein and a consensus profile of 5 Hitler experts was r = .79, indicating a very strong similarity between the two profiles. It was concluded that Saddam Hussein had many of the same personality disorders or their features as Adolf Hitler, although sadistic features were stronger in Hussein than Hitler. It appeared that a “Big Four” personality disorders constellation emerged for these two dictators, and they were sadistic, antisocial, paranoid, and narcissistic. It was also found that Hussein might have had some traits or features of paranoid schizophrenia. Implications for diplomacy and negotiations with persons with similar personality profiles are proffered. 相似文献
979.
980.