Nature of ferroelectric–paraelectric transition

Ferroelectric (FE) materials directly convert electrical energy to mechanical energy and are critical to applications such as sensors, transducers, and actuators. The giant electromechanical response is the manifestation of the critical point between the first-order and second-order ferroelectric–paraelectric (FE–PE) transitions. For the simple classic FE lead titanate (PbTiO₃), it is commonly accepted that there is a critical point in the temperature–pressure phase diagram separating the first- and second-order FE–PE transitions at zero electric field. Here, we show that the FE-PE transition in PbTiO₃ is second-order at zero electric field. We introduce the concept of the invariant critical points (ICP) among three phases, representing the stability of the PE phase with respect to two FE phases in a three-dimensional electric field-pressure-temperature phase diagram of PbTiO₃. It is pointed out that the electromechanical response near ICPs is larger than that near the line of critical end points (LCEPs) between two phases.     

Bending experiments on the xi'-(Al-Pd-Mn) quasicrystal approximant

Single crystals of the quasicrystal approximant phase xi'1-(Al-Pd-Mn) were deformed at a high temperature in three-point bending geometry. Two different mechanisms of plastic deformation were observed in this phase: one based on the motion of phason lines and the other based on dislocations. Line directions and Burgers vector directions of the dislocations were determined. The relative importances of the two mechanisms are discussed as a function of the sample orientation with respect to the bending geometry.     

Strain-induced submicrocrystalline grains developed in austenitic stainless steel under severe warm deformation

Strain-induced grain evolution in a 304 type austenitic stainless steel has been studied in multiple compression with the loading direction being changed in each pass. The tests were carried out to total strains above 6 at 873 K (0.5 T _m) at a strain rate of about 10^-3 s^-1. Multiple deformation promotes the rapid formation of many mutually crossing subboundaries because various slip systems operate from pass to pass. The gradual rise in misorientations across dislocation subboundaries with increasing strain finally leads to the evolution of very fine grains with large-angle boundaries. It is concluded that a new grained structure can result from a kind of continuous reaction during deformation, namely continuous dynamic recrystallization. Such deformation-induced grains are characterized by relatively low densities of dislocations, and considerable lattice curvatures developed in their interiors. The latter observations suggest that high elastic distortions are developed in the grain interiors and so such strain-induced grain structures are in a non-equilibrium state.     

Coparenting Negotiation During the Transition to Parenthood: A Qualitative Study of Couples’ Experiences as New Parents

Abstract

Coparenting – how couples relate to one another in their joint roles as parents – is predictive of a wide variety of family and child outcomes. The current study used a qualitative, phenomenological approach to understand how couples negotiate the coparenting relationship during the transition to parenthood. The principal researcher interviewed 16 men and women of eight heterosexual, dual-earning, new parent couples. Themes emerged which were both conducive to successful coparenting and inhibitive of successful coparenting. Gender distinctions emerged between men and woman in their experiences of coparenting negotiation. Clinical implications of the themes are discussed.     

Noogenesis—the fundamental problem of our time

The possibility of long wave economic cycles are considered under both market capitalism and command socialism. Capitalist long waves can be generated by a two‐stage multiplier‐accelerator model and socialist long waves can be generated by an equivalent model strictly for investment cycles. Under certain conditions chaotic dynamics can occur at turning points in both cases. It is argued that a systemic crisis leading to a systemic transformation is most likely to occur at such a point.     

Discrete Process Model for Quantum Systems of Matter and Mind

Attempts to create a coherent scientific picture of the world as a whole on the basis of quantum physics has sped up at the turn of the millennium. There particularly seem to be expectations that the development of a new kind of quantum mechanics could make it possible to describe both matter and consciousness in one frame of reference (“dual aspect approach”). These ideas are often results of brilliant intuitive visions but as yet not able to produce testable hypotheses. Maybe “wave mechanics” is not very suitable in the study of consciousness from the quantum mechanical point of view. The aim of this article is to show how both the matter and the mind systems can be described with one coherent mathematical model if we assume both space and time to be discrete.     

Action-control beliefs and behaviors as predictors of change in adjustment across the transition to middle school

Abstract

We examined longitudinal changes in young adolescents’ (N=368) action-control beliefs, coping behaviors, and adjustment (i.e., positive and negative affect, depression, aggression) across the transition from elementary school to middle school. Results indicated greater inter-individual instability in adjustment during this transition than during the previous school year. Using ordinary least-squares (OLS) growth models to extract intra-individual change scores for each variable (i.e., slopes and intercepts), we conducted a series of stepwise regressions to determine which features of control beliefs and coping behaviors best predicted changes in adjustment across the transition to middle school. We found that negative coping behaviors (i.e., antisocial coping) consistently predicted negative changes in the adjustment variables (e.g., greater depression, more aggression), whereas positive beliefs and behaviors did not consistently predict changes in the adjustment variables.     

Interlimb Coordination During Step-to-Step Transition and Gait Performance

Most energy spent in walking is due to step-to-step transitions. During this phase, the interlimb coordination assumes a crucial role to meet the demands of postural and movement control. The authors review studies that have been carried out regarding the interlimb coordination during gait, as well as the basic biomechanical and neurophysiological principles of interlimb coordination. The knowledge gathered from these studies is useful for understanding step-to-step transition during gait from a motor control perspective and for interpreting walking impairments and inefficiency related to pathologies, such as stroke. This review shows that unimpaired walking is characterized by a consistent and reciprocal interlimb influence that is supported by biomechanical models, and spinal and supraspinal mechanisms. This interlimb coordination is perturbed in subjects with stroke.     

Examining Patterns of Political, Social Service, and Collaborative Involvement of Religious Congregations: A Latent Class and Transition Analysis

This investigation examines typologies of congregations based on patterns of congregational political and social service activities and collaborative partners. Based on a latent class analysis of a national random sample of 2,153 congregations, results indicated four distinct types of congregations with unique patterns of political, social service, and collaborative partnerships labeled: (a) Active, (b) Not Active, (c) Social Service Not Political, and (d) Political Not Social Service. Moreover, congregational characteristics such as religious tradition and clergy characteristics predicted membership in certain types. A latent transition analysis using an additional 262 congregations revealed distinct patterns of how congregations changed types across a nine year period. Results showed both congregational continuity (e.g., Not Active congregations remained Not Active) and change (e.g., Active congregations were likely to change type membership). This study advances congregational research by examining congregational types, what predicts certain types, and how congregations change types across time. Implications for future research and partnership with religious congregations also are discussed.     

Behavioral Assessment in the Schools:

This article discusses behavioral assessment as a way of obtaining and evaluating information used to individualize programming for special needs pupils. Behavioral assessment offers a range of techniques for gathering and for evaluating information. Strategies for obtaining information that are described are self-monitoring, direct observation, permanent product review, and retrospective ratings using behavior checklists. Strategies for evaluating information that are discussed are single-case research designs and social validation. These strategies assist in identifying pupil problems and selecting interventions, evaluating student progress, assessing treatment fidelity, determining causality, and revising individualized programs by providing a broad base for decision-making.