Study of ferroelectric nanodomains and the effect of grain size in BaTiO3 ceramics

Nanodomains and grain-size effects in BaTiO₃ have been studied theoretically. In this article, we have calculated the long-range Coulomb interaction between ferroelectric nanodomains in a single BaTiO₃ grain, and obtained information on the domain structure at various temperatures and grain sizes. The relation between transition temperature and the grain size is obtained by incorporating the domain-wall energy, the surface energy, and the stress energy into the Landau–Ginzburg free-energy density. The results show that 180° domains exist in ferroelectric BaTiO₃ nanoceramics. At room temperature, with the decreasing grain size, the domain width does not decrease monotonically; when the grain size reduces to 18?nm, the grain becomes a single domain, and when less than 12?nm, the ferroelectric phase disappears. With the decreasing grain size the temperature of the cubic-tetragonal phase transition is reduced, while the temperatures of the tetragonal–orthorhombic and orthorhombic–rhombohedral phase transitions reach a maximum when the grain sizes are in the vicinity of 200?nm. The theoretical results are compared with experimental data.     

Predicting children's academic achievement after the transition to first grade: A two-year longitudinal study

The transition from kindergarten to first grade has been described as a critical period for children's academic development. Furthermore, research indicates that peer status is connected with academic adjustment, yet the underlying processes remain unclear. By means of a two-year longitudinal study during kindergarten and first grade (N = 153), we aimed to shed light on the antecedents of achievement at the end of first grade. Based on the parallel processes mediation model (Buhs, 2005), a comprehensive predictive model was constructed and tested. Results showed that (a) the parallel processes mediation model is partially valid during the transition from kindergarten to first grade; and (b) there is more support for an effect of academic self-concept on achievement than vice versa. This comprehensive model increases our insight in the factors that enhance children's academic development during the transition to first grade.     

Transitioning between work and family roles as a function of boundary flexibility and role salience

This study investigates the manner in which people separate their work and family roles and how they manage the boundaries of these two important roles. Specifically, we focus on how role flexibility and salience influence transitions between roles. Results indicate that the ability and willingness to flex a role boundary and role salience are important predictors of transitions between roles. The joint effects of role flexibility and salience on transitions provided interesting results regarding the importance of role boundary flexibility and of the increasing importance attached to the family role. Limitations, suggestions for future research, and implications are discussed.     

A RESPONSE TO CARL HELRICH: THE LIMITATIONS AND PROMISE OF QUANTUM THEORY

Abstract. I respond to Carl Helrich's criticism of my proposition that the emergence of complex order in the universe is from Virtual State Actualization (VSA). The question is discussed as to whether quantum theory is able to afford any kind of quantum ontology or whether it merely allows an epistemological view. I point out that, even though many contradictory interpretations of quantum theory are currently possible, the concept of VSA is based on molecular properties that are so simple and factual that they are beyond interpretation. Helrich's appeal for caution in proceeding from physical reality to Divine Reality is wholeheartedly supported and a detailed discussion is given.     

A RESPONSE TO STANLEY KLEIN: A DIALOGUE ON THE RELEVANCE OF QUANTUM THEORY TO RELIGION

Abstract. I respond to Stanley Klein's critique of my essay “Quantum Reality, the Emergence of Complex Order from Virtual States, and the Importance of Consciousness in the Universe,” arguing in support of the necessity to derive a quantum perspective of evolution rather than adhering to an essentially classical view. In response to Klein's criticism of my concept of a cosmic morality, the origins of that concept are traced back to Zeno of Citium. I wholeheartedly embrace Klein's suggestion that the new science inspires views of the human condition that can help us make the world a better place.     

USING HIGH-PROBABILITY INSTRUCTION SEQUENCES WITH FADING TO INCREASE STUDENT COMPLIANCE DURING TRANSITIONS

Making efficient transitions from one instructional activity to another has been shown to increase academic learning time and therefore student achievement. Because compliance with teacher instructions is a prerequisite for efficient transitions, we sought to determine if high-probability (high-p) instruction sequences issued by a classroom teacher would increase student compliance and decrease latency to comply during transitions. Three children in a regular second-grade classroom participated. Each day at the beginning of morning calendar time, the teacher issued five instructions to the class as a group while compliance data were recorded for the 3 target students. Following baseline, a multielement design was used to examine the effects of the high-p instruction sequence. We then systematically faded the number of instructions included in the high-p sequence as a means of transferring stimulus control to low-probability instructions. The procedure was effective for 2 of the 3 participants, and the results were maintained at 2-and 3-week follow-up. The implications of these findings for group applications of the high-p instruction sequence in regular education classrooms are discussed.     

A translational evaluation of transitions

Transitions with nonhuman animals are typically framed as inescapable changes in signaled reinforcement schedules that result in a pause in responding unique to switches from rich to lean schedules. Pausing is considered to be a function of the aversive qualities of the contrasting reinforcement schedules. Transitions are typically framed in applied research as physical changes in location that evoke problem behavior maintained by the escape of an aversive event or resumption of a preferred event. We attempted to extend the basic framing of transitions to behaviors and contexts of social significance and evaluate a novel treatment for the problem of dawdling by 3 boys who had been diagnosed with autism spectrum disorder during rich‐to‐lean transitions. Dawdling during physical transitions was most readily observed when transitioning to lean contexts in Experiment 1. We then shortened transition duration in Experiment 2 by programming unsignaled and probabilistic rich reinforcement in the upcoming context.     

Developmental pathways of behavior problems in the young child: factors associated with continuity and change

The continuity and discontinuity of behavioral problems from age 4 through age 7 until 10 were examined in 120 children. The mothers rated childhood behavior problems at the three age points. Problems were defined as above 80th percentile. Individual transition classification of problematic and non-problematic children showed that 7% had stable behavior problems, 60% stable non-problematic behavior and the rest displayed transitions related to either onset or offset of problems. The mechanisms involved in onset were different from those involved in offset. Children showing onset of problems had fewer friends, participated less often in organized leisure activities and were more passive in class than the well-functioning children. Maternal characteristics such as continued education, current employment and high educational ambitions for the child were associated with having children changing their pathway from risk to an adaptive one.     

Why is it so hard to do my work? The challenge of attention residue when switching between work tasks

In many jobs, employees must manage multiple projects or tasks at the same time. A typical workday often entails switching between several work activities, including projects, tasks, and meetings. This paper explores how such work design affects individual performance by focusing on the challenge of switching attention from one task to another. As revealed by two experiments, people need to stop thinking about one task in order to fully transition their attention and perform well on another. Yet, results indicate it is difficult for people to transition their attention away from an unfinished task and their subsequent task performance suffers. Being able to finish one task before switching to another is, however, not enough to enable effective task transitions. Time pressure while finishing a prior task is needed to disengage from the first task and thus move to the next task and it contributes to higher performance on the next task.     

Seeking sacred pathways: How ritual is being used as a means for spiritual support

ABSTRACT

Baby boomers are confronting new life stages as they navigate the revolution in longevity. Emerging in this journey are new rituals and reinterpretations of old ones that speak to these new life stages. These rituals help provide a grounding and guide to create moments of meaning as we encounter our own aging.