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101.
This letter presents a study of the atomic mechanism of the initiation of motion of a static twin plane under applied mechanical load in a model shape-memory material. By tracking the deformation under load and using linear stability analysis, we find that the eigenvalues of the Hessian matrix provide an indicator of the initiation of motion of the twin plane. The initiation of motion is signaled by a linear instability and a drop in the lowest eigenvalue to zero as well as a sharp drop in higher eigenvalues. Additionally, by comparing with direct molecular dynamics, we see that the eigenmode associated with the zero eigenvalue is found to accurately predict the initial mode of motion. We also find that the initial motion occurs through the formation of a stacking fault just ahead of the existing twin plane and the broadening of the stacking fault drives further transformation.  相似文献   
102.
Overgeneral autobiographical memory (OGM) is a proposed trait-marker for vulnerability to depression, but relatively little work has examined its long-term stability. This study investigated the stability of OGM over several years in 271 late adolescents and young adults participating in a larger longitudinal study of risk for emotional disorders. The Autobiographical Memory Test (AMT) was administered twice, with test–retest intervals ranging from approximately 3 to 6 years. There was evidence of significant but modest stability in OGM over several years. Specifically, Spearman rank correlations (ρs) between the proportions of specific and categoric memories generated on the two AMTs were .31 and .32, respectively. We did not find evidence that the stability of OGM was moderated by the length of the test–retest interval. Furthermore, the stability coefficients for OGM for individuals with and without a lifetime history of major depressive disorder (MDD) were relatively similar in magnitude and not significantly different from one another (ρs=.34 and .42 for the proportions of specific and categoric memories for those with a history of MDD; ρs=.31 for both the proportions of specific and categoric memories for those without a history of MDD). Implications for the conceptualisation of OGM are discussed.  相似文献   
103.
Drawing from the perspective of an interdisciplinary exploration of the sociocultural impact of the printing press and its effects on Catholic thinkers, educators, and worship practices, the author of this article explores the educational mission of Catholic publishing during the Reformation and how it has evolved in modern times. First, the author discusses the communication dynamics of the Reformation and specifically the impact of the printing press. Second, the author explores the historical reasons for why the Roman Church perceived the need for uniformity in worship. Third, the author focuses on how the Roman Church built upon this framework of uniformity to define and shape the issues that were being discussed when expanding their outreach to the public during this period. Fourth, the author shows how Catholic worship and education evolved within an interpretation that is relevant to the educational mission of Catholic publishers today.  相似文献   
104.
Reduced support-surface stability has been shown to attenuate the effect of Achilles tendon vibration on backward body displacement. In the present study, 20 participants performed a quiet, upright standing task on a stable and sway-referenced support, with and without vibration. The authors calculated equilibrium scores (ES), approximate entropy (ApEn), and mean and peak power spectral density frequencies of center-of-pressure variations. It was found that ES values decreased with the addition of vibration and in the sway-referenced support condition. ApEn values decreased with the addition of vibration but only with a stable support. Conversely, mean and peak frequencies increased with the addition of vibration, independent of support stability. These results suggest that the role of ankle proprioceptive input changes depending on support-surface characteristics and demonstrate the value of using both linear and nonlinear measures of postural sway.  相似文献   
105.
From among the diverse meanings of stability, the one the author adopts here is that the effects of a perturbation are opposed, and therefore small effects remain small. Except in linear systems, however, instability need not lead to unbounded motion and may actually be desirable when maneuverability is important. Moreover, properties of nerves, muscles, and tendons present serious challenges to stabilization. A review of observations from the motor control literature reveals that responses to perturbations in many common situations assist rather than resist the perturbation and are therefore presumably destabilizing. The observations encompass situations of position maintenance as well as impending or ongoing movement. The author proposes that the motor control system responds to a sudden perturbation by a pattern of muscle activity that mimics an accustomed voluntary movement, oblivious of stability considerations. What prevents runaway motion in the face of short-term instability appears to be voluntary intervention.  相似文献   
106.
The integral age demands a new economic vision. This has to emphasize exchange as a processes not the exchange of things. It must address humanity's unique compulsion to learn using collaborative learning networks. These are what energize the self-organizing global change now accelerating the emergence of new global economic institutions and processes. This new vision requires political economy (i.e., economics integrated with its sociopolitical context).  相似文献   
107.
The state and federal governments, along with private industry, play an important role in the development of a health profession. State governments establish training standards through licensure laws, and state programs dictate employment and payment opportunities. The federal government unifies a profession through recognition in national health care programs. Private industry provides public access through private health insurance. The counseling profession has spent decades opening these federal, state, and private programs to become an established health profession.  相似文献   
108.
Do actual and perceived self‐enhancement entail differing social impressions (i.e. interpersonal evaluations)? Actual self‐enhancement represents unduly positive self‐views, as gauged by an objective criterion (in this case, IQ scores), whereas perceived self‐enhancement involves the extent to which an individual is seen by informants (i.e. peers or observers) as self‐enhancing. In an online survey (N = 337), a laboratory experiment (N = 75), and a round‐robin study (N = 183), we tested the effects of actual and perceived intellectual self‐enhancement on (informant‐rated) emotional stability, social attractiveness, and social influence. Actual self‐enhancers were rated as emotionally stable, socially attractive, and socially influential. High perceived self‐enhancers were judged as socially influential, whereas low‐to‐moderate perceived self‐enhancers were deemed emotionally stable and socially attractive. Privately entertained, illusory positive (even extreme) self‐beliefs confer social benefits, whereas being perceived as self‐enhancing buys social influence at the cost of being despised. Copyright © 2013 European Association of Personality Psychology  相似文献   
109.
We assessed the stability of a short-form six-factor personality measure over a one-year period in a large national probability sample (N = 4289). Personality was assessed using the Mini-IPIP6—a short-form measure assessing Extraversion, Agreeableness, Conscientiousness, Neuroticism, Openness to Experience, and Honesty-Humility. Standardized estimates calculated using Bayesian Structural Equation Modelling (BSEM) indicated that all six personality dimensions were extremely stable. An alternative model using Maximum Likelihood estimation, in which residual item variances were associated over repeated assessments, yielded similar findings. These results highlight the stability of personality in the general population, even when assessed using short-form scales. The use of Bayesian models to examine the stability of personality and their application for study of change in specific developmental periods is discussed.  相似文献   
110.
In times of war, news media coverage of the plight of civilian casualties plays a critical role in shaping attitudes regarding war's human costs. We proposed that these attitudes may also be surreptitiously influenced by the commercial advertisements that often accompany this coverage. Specifically, we hypothesized that when newspaper articles pertaining to civilian victims of war are flanked by luxury ads, conservatives, relative to liberals, will subsequently exhibit less concern for these victims. This proposition was based on the notion that commercial ads, particularly those promoting luxury items, make salient the gap between the “haves” and the “have‐nots” and thereby, at least implicitly, threaten the legitimacy of the current socioeconomic system. Drawing upon system justification theory, we posited that this threat would lead individuals with stronger system‐justification tendencies (conservatives), relative to those more open to challenging the current system (liberals), to show greater tolerance for civilian war casualties in order to defend the system's integrity. Evidence consistent with this hypothesis was found in a quasi‐experimental study (n = 329).  相似文献   
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