Perception and action in swimming: Effects of aquatic environment on upper limb inter-segmental coordination

This study assessed perception–action coupling in expert swimmers by focusing on their upper limb inter-segmental coordination in front crawl. To characterize this coupling, we manipulated the fluid flow and compared trials performed in a swimming pool and a swimming flume, both at a speed of 1.35 m s⁻¹. The temporal structure of the stroke cycle and the spatial coordination and its variability for both hand/lower arm and lower arm/upper arm couplings of the right body side were analyzed as a function of fluid flow using inertial sensors positioned on the corresponding segments. Swimmers’ perceptions in both environments were assessed using the Borg rating of perceived exertion scale. Results showed that manipulating the swimming environment impacts low-order (e.g., temporal, position, velocity or acceleration parameters) and high-order (i.e., spatial-temporal coordination) variables. The average stroke cycle duration and the relative duration of the catch and glide phases were reduced in the flume trial, which was perceived as very intense, whereas the pull and push phases were longer. Of the four coordination patterns (in-phase, anti-phase, proximal and distal: when the appropriate segment is leading the coordination of the other), flume swimming demonstrated more in-phase coordination for the catch and glide (between hand and lower arm) and recovery (hand/lower arm and lower arm/upper arm couplings). Conversely, the variability of the spatial coordination was not significantly different between the two environments, implying that expert swimmers maintain consistent and stable coordination despite constraints and whatever the swimming resistances. Investigations over a wider range of velocities are needed to better understand coordination dynamics when the aquatic environment is modified by a swimming flume. Since the design of flumes impacts significantly the hydrodynamics and turbulences of the fluid flow, previous results are mainly related to the characteristics of the flume used in the present study (or a similar one), and generalization is subject to additional investigations.     

An ethnographic inquiry of cooperative learning implementation

Qualitative research methods were employed to explore variations in teacher implementation of a research-based model of cooperative learning. Participants included five middle school math and science teachers who were trained in the Johnson, D.W. and Johnson, R.T. [Johnson, D. W., & Johnson, R. T. (1983). The socialization and achievement crisis: Are cooperative learning experiences the answer? Applied Social Psychology, 4, 199-124.] model of cooperative learning. Implementation was examined via interview and observation. Principles from cognitive psychology defined constructs for study, which included teacher concepts, plans, and enactment of cooperative learning in the classroom. Study design included features characteristic of ethnographic inquiry: prolonged engagement, purposeful sampling, persistent observation, multiple source data collection, and recursive interpretation. Triangulation of data sources revealed that relationships between concepts, plans and enactment were mediated by teaching style, teaching context, and degree of teaching expertise. Findings suggest that when attempting to implement cooperative learning lessons, teacher may benefit from attention to teacher and student roles, curricular requirements, instructional time, and classroom management skills. Findings further demonstrate the important contributions of qualitative research to the cooperative learning literature.     

Failing to come to terms with things: a multi‐storied conversation about poststructuralist ideas and narrative practices in response to some of life's failures

This paper is designed to demonstrate some of the multi‐storied representational possibilities available to us as writers and practitioner‐researchers. It highlights some of the opportunities that are available to therapists and the people who consult them when they describe their conversational space as a site for co‐research. It illustrates the reciprocity present in conversations, including therapeutic conversations, by juxtaposing three stories that are interrelated retellings from different writing genres. In positioning poetic, storied and more academic/interpretative texts alongside each other, we hope to trouble the edges between academic and creative writing and also between practice and research. In placing these stories next to each other we seek to disrupt carefully contained ‘client’ and ‘therapist’ positions. We intend to question some current bereavement orthodoxies by demonstrating some less taken‐for‐granted ways in which people, living and dead, can and do continue to sustain each other's lives. We also hope to invite the readers and future writers of this journal to play alongside us in this conversation.     

An Ecological Process Model of Systems Change

In June 2007 the American Journal of Community Psychology published a special issue focused on theories, methods and interventions for systems change which included calls from the editors and authors for theoretical advancement in this field. We propose a conceptual model of systems change that integrates familiar and fundamental community psychology principles (succession, interdependence, cycling of resources, adaptation) and accentuates a process orientation. To situate our framework we offer a definition of systems change and a brief review of the ecological perspective and principles. The Ecological Process Model of Systems Change is depicted, described and applied to a case example of policy driven systems level change in publicly funded social programs. We conclude by identifying salient implications for thinking and action which flow from the Model.     

特需医疗服务供方意向调查分析

剖析目前特需医疗服务供方所存在的主要问题,初步探讨在我国发展特需医疗服务适宜的承担主体。采用个别访谈和问卷调查的方法对来自不同性质的医院的医护人员和医院管理人员进行了意向调查。结果显示,医院发展特需医疗服务并不是解决医务人员收入问题的有效手段;公立医院发展特需医疗服务势必会对其普通医疗服务带来负面影响。建议在确保大部分公立医院只提供普通医疗服务的基础上,由私立医院和一部分公立医院作为特需医疗服务的承担机构。     

New Perspectives on the Child‐ and Youth‐Serving Workforce in Low‐Resource Communities: Fostering Best Practices and Professional Development

The professionals and paraprofessionals who work daily with youth in low‐resource, marginalized communities are integral to youth wellbeing; yet, their professional development, and the factors that promote it, are not well understood. In this introduction to the special issue, Understanding and Strengthening the Child‐ and Youth‐Serving Workforce in Low‐Resource Communities, we focus on understudied practitioners operating in an array of sectors and settings, such as home visitors, mental health paraprofessionals, early childhood assistant teachers, teachers in low‐income countries, school resource officers, juvenile justice staff, and after‐school and community‐based program workers. We put forward a conceptual model detailing the interactive, layered set of proximal‐to‐distal ecological factors that influence the practice and professional development of these workers, and show how papers in the current issue address these layers in their examination of workforce development. We conclude with a summary of the contributions and lessons from this work – including the value of a whole‐person approach, the importance of sharing process across research stages, and the need to build on the foundation provided by community psychology and implementation science – toward the twin goals of understanding and building the skills and strengths of the workforce, and ultimately, enhancing youth development.     

Social Cohesion,Neighborhood Collective Efficacy,and Adolescent Subjective Well‐being in Urban and Rural Taiwan

This study investigates the association between neighborhood social cohesion, collective efficacy, and adolescent subjective well‐being in a nationally representative sample of Taiwanese youth. The study represents a first to adapt and test a developmental ecological model within a Chinese cultural context. Data came from the Taiwan Youth Project, which assessed representative samples of seventh graders (n = 2,690) and ninth graders (n = 2,851) from both urban and rural counties. The analytic sample included 4,988 adolescents (M age = 14.4, SD = 1.14; 50% female) in Taiwan. A path analysis estimated the direct and indirect effects of social cohesion on adolescent well‐being. The results suggest that neighbors can affect young people's well‐being by reinforcing their perception of safety and enhancing their self‐esteem. Comparisons between youth from urban and rural areas demonstrate a general similarity in the developmental processes, though the perception of safety is less of a concern in rural areas. Findings emphasize universal aspects of neighborhood collective efficacy and developmental–ecological models, as well as allude to culturally specific dimensions in a Chinese‐based context.     

Training programme designs in professional team sport: An ecological dynamics exemplar

Ecological dynamics is a contemporary theory of skill acquisition, advocating the mutuality of the performer-environment system, with clear implications for the design of innovative training environments in elite sport. It contends that performance behaviours emerge, and are adapted, by athletes satisfying a confluence of constraints impacting on their structural and functional capacities, the physics of a performance environment and the intended task goals. This framework implicates contemporary models of coaching, training design and sport science support, to stimulate continuous interactions between an individual and performance environment, predicated on representative learning designs (RLD). While theoretical principles of RLD in ecological dynamics are tangible, their practical application in elite and high level (team) sports need verification. Here, we exemplify how data sampled from a high-performance team sport setting could underpin innovative methodologies to support practitioners in designing representative training activities. We highlight how the use of principles grounded within ecological dynamics, along with data from performance analytics, could suggest contemporary models of coaching and preparation for performance in elite sport.     

Walking with avatars: Gait-related visual information for following a virtual leader

Dynamic situations, such as interactive sports or walking on a busy street, impose high demands on a person’s ability to interact with (others in) its environment (i.e., ‘interact-ability’). The current study examined how distance regulation, a fundamental component of these interactions, is mediated by different sources of visual information. Participants were presented with a back and forwards moving virtual leader, which they had to follow by walking back and forwards themselves. We presented the leader in several appearances that differed in the presence of segmental (i.e., relative movements of body segments), cadence-related (i.e., sway and bounce), and global (i.e., optical expansion-compression) information. Results indicated that removing segmental motion information from the virtual leader significantly deteriorated both temporal synchronization and spatial accuracy of the follower to the leader, especially when the movement path of the leader was less regular/predictable. However, no difference was found between cadence-related and global motion information appearances. We argue that regulating distance with others effectively requires a versatile attunement to segmental and global motion information depending on the specific task demands. The results further support the notion that detection of especially segmental information allows for more timely ‘anticipatory’ tuning to another person’s locomotor movements and intentions.