Demonstration and interpretation of ‘scutoid’ cells formed in a quasi-2D soap froth

ABSTRACT

Recently a novel type of epithelial cell has been discovered and dubbed the ‘scutoid’. It is induced by curvature of the bounding surfaces. We show by simulations and experiments that such cells are to be found in a dry foam subjected to this boundary condition.     

Thermodynamic fluctuations in magnetic states: Fe3Pt as a prototype

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.     

A theory of work softening

Observed features of the yield drop in work softening support the view that the structure in a slip band is heterogeneous in a metal such as aluminium or copper. The centre of the band is almost empty of dislocations. These are concentrated round its boundary, particularly as walls of edge dipoles at its ends. It is argued that work hardening is due to the prevention of the passage of these dislocations by a forest of obstacles with small activation volumes and energies. Thermal energy enables them to cut through their obstacles and so to penetrate further into their walls, thereby reducing their back stress and enabling the Frank-Read sources, within the bands, to become active at lower applied stresses. The yield drop is explained as due to an overshooting, resulting from this thermally activated cutting, of the stress to operate the sources.     

The role of career values for work engagement during the transition to working life

The present longitudinal study examined the role of career values for work engagement across the transition from university education to working life. Finnish young adults reported on their career values (intrinsic, rewards, and security values) at the age of 23; and the degree of person–organization fit (value congruence, and congruence between one's education and the job), subjective income and economic stress two years later at the age of 25. Work engagement was assessed at both measurement points. Structural equation modeling results showed, first, that intrinsic but not rewards or security career values were related to work engagement. Second, value congruence and having a job which was related to young adults' educational field were positively associated with work engagement. Our findings suggest that along with person–organization fit, intrinsic career values are a significant factor in shaping and facilitating successful transitions from education to work.     

Determinants of coach motivation and autonomy supportive coaching behaviours

ObjectiveThe objective of the present study is to build upon the existing literature examining the coaching context and how it relates to coaches' use of autonomy-supportive interpersonal behaviours (i.e. Stebbings, Taylor, Spray, & Ntoumanis, 2012) by identifying additional environmental factors and exploring the role of coach motivation.DesignAn academic model designed by Pelletier, Seguin-Levesque, and Legault (2002) to predict teacher motivation and autonomy-supportive styles in academic settings, was adapted to the coaching context.MethodsThe influence of pressure from above (sport administrations) and pressure from below (athlete motivation) on coach motivation and autonomy-supportive coaching behaviours was tested using structural equation modeling.ResultsResults support the fit of the model in a sport context.ConclusionsPressure from above, pressure from below, and coach motivation predict coaches’ reported use of autonomy-supportive behaviours.     

Change in physical self-perceptions across the transition to secondary school: Relationships with perceived teacher-emphasised achievement goals in physical education

ObjectivesThis study aimed to examine the effects of change in perceived teacher achievement goal emphasis in physical education (PE) on physical self-perceptions and self-esteem across the transition to secondary school.Design & methodsA longitudinal design was adopted with three time points, one at the end of primary school and two during the first year of secondary school. Participants (N = 491) were cross-classified by primary (N = 42) and secondary (N = 46) PE class in order to examine the association between perceived class-level teacher-emphasised goals and within-class student goals with self-beliefs.ResultsPersonal approach goals and class perceptions of teacher mastery approach goal promotion were all positively associated with ratings of co-ordination, sport competence, flexibility, and endurance in primary school. More favourable perceptions of coordination, sport competence, strength, flexibility, and endurance during the first year of secondary school were predicted by an increase in performance approach goal emphasis, whereas ratings of sport competence and flexibility were negatively associated with an increase in mastery approach goal emphasis.ConclusionsAlthough not entirely consonant with theoretical predictions, current findings suggest that teacher-emphasised performance approach goals in PE can promote development of several physical self-perceptions in the initial year of secondary school.     

Burnout and its relations with basic psychological needs and motivation among athletes: A systematic review and meta-analysis

ObjectivesThe present study is a review on studies about the relationships between the three basic psychological needs/motivational regulations (i.e., amotivation, controlled regulation, extrinsic autonomous regulation, and intrinsic motivation) and burnout.DesignA systematic review and meta-analysis.MethodStudies were identified through five electronic databases and manual search using combinations of three groups of keywords. Three inclusion criteria were then used to screen the searched articles.ResultsEighteen studies met the inclusion criteria and these studies varied considerably in terms of their study characteristics (e.g., characteristics of participants, study designs, and outcome measures). The results also showed that the three basic psychological needs, intrinsic motivation, extrinsic autonomous regulation, and amotivation had small to large effects on predicting global burnout and its three dimensions. However, controlled regulation showed no or weak correlations with the burnout subscales.ConclusionsSelf-determination theory was generally supported in explaining athlete burnout.     

The effect of performance setting and individual differences on the anxiety-performance relationship for elite cyclists

Fifty-three national level cyclists completed competitive rides under both laboratory and field conditions to investigate the relationship between pre-competition anxiety and performance. A total of 39 males and 14 females participated in the study, ranging in age from 19 to 26. The objectives of the study were to, (a) measure the relationship between state anxiety and performance, (b) investigate differences in the anxiety-performance relationship under laboratory versus field conditions, and (c) examine the effect of trait anxiety on the state anxiety-performance relationship. State anxiety was measured using the Competitive State Anxiety Inventory-2 (CSAI-2; Martens, Vealey, & Burton, 1990), and trait anxiety with the State-Trait Anxiety Inventory (STAI; Spielberger, Gorsuch, & Lushene, 1970). Results indicated that anxiety was strongly correlated with performance on the field test, but that the anxiety-performance relationship was weaker under laboratory conditions. Results also showed that trait anxiety interacted with the relationship, as low and high trait-anxious subjects had differential response patterns to pre-competition anxiety. The findings are discussed in terms of their relevance for both practitioners and researchers.     

Inconsistent child-rearing: A reply to rosenthal

Abstract

In a reply to our paper (Kohlmann, Schumacher, & Streit, 1988), Rosenthal (in a Letter to the Editors, this issue) primarily gives some comments on findings regarding the association of inconsistent child-rearing behavior and anxiety in the child. Results of our study were compared to results from a study by Rosenthal, Finkelstein, Ni, and Robertson (1959).     

Athletes' perceptions of how cognitive interference during competition influences concentration and effort

Abstract

This paper investigates athletes' perception of the relationship between cognitive interference and its effects on concentration and effort during sport performance. The sample consisted of 115 volleyball players that took part in a national university tournament. Three different kinds of thoughts were investigated: ‘performance worries’, ‘situation-irrelevant thoughts’, and ‘thoughts of escape’. Path analysis was used to examine the relationships. All kinds of thoughts were reported to be detrimental to concentration, whereas different patterns of associations emerged between different thoughts and subsequent effort. ‘Performance worries’ were reported to be related to increases in effort for athletes holding higher goal attainment expectancies and decreases in effort for athletes holding lower goal attainment expectancies. ‘Thoughts of escape’ were reported to be related to decreases in effort, while no significant relation between ‘situation irrelevant thoughts’ and effort emerged. Results stress the importance of further examining the role of interfering thoughts athletes experience during competition.