Essential gyrators and reciprocity in junction structures

This paper proposes an extended definition of reciprocity for a multiport junction structure based on the concept of essential gyrator coupling. Two theorems are given for junction structures containing gyrators and an algorithm is presented for identifying essential gyrators. The results are useful both theoretically and for designing efficient computation procedures for junction structures.     

Trends and practices in functional behavior assessments completed by school psychologists

Functional Behavior Assessments (FBAs) utilize direct and indirect methods to collect data on student behavior to generate a functional hypothesis and drive intervention development. School psychologists are trained to conduct FBAs and use them regularly in schools. However, no evidence exists describing the specific practices used by school psychologists when they conduct FBAs. In this study, 199 respondents completed a web‐based survey developed using expert review and cognitive pretesting. Most respondents reported their gender as female (87%), were between 30 and 39 years old (50%), and practiced at the Specialist level (57%). Respondents reported receiving training in FBA across multiple sources and utilizing multi‐method data collection methods when conducting FBAs. A large amount of variability was observed in the specific instruments used by school psychologists, with a substantial proportion using forms that were not standardized or pre‐constructed. Implications for current practitioners, trainers, and researchers are described.     

The influence of race length on arterial compliance following an ultra-endurance marathon

There is inconclusive evidence concerning the effects of routine participation in ultra-endurance events on cardiovascular disease (CVD) risk. Arterial compliance is a reliable, non-invasive, and effective tool for evaluating CVD risk. The purpose of this research was to examine if race length influences acute changes in arterial compliance following an ultra-marathon event. A total of 46 ultra-marathon runners were recruited including 21 participants (39.8?±?8.3?years, 6 females) in the 80-km event and 25 participants (43.7?±?9.8?years, 3 female) in the 195-km event. Arterial compliance was measured via radial applanation tonometry (CR-2000, HDI) for diastolic pulse contour analysis before and following the race. Significant between-group differences were found for changes in large arterial compliance with a decrease (increase in stiffness) following the 195-km event and an increase following the 80-kilometre event (p?<?.05). Longer race lengths are associated with greater reductions in large arterial compliance following recreational ultra-marathon running. Assessment of arterial compliance might be a useful prognostic tool to assess the long-term risk of CVD among ultra-marathon runners.     

The link between student-perceived teacher talk and student enjoyment,anxiety and discursive engagement in the classroom

This study seeks to understand the emotional connection of teachers' academically productive talk (APT) with student learning from the students' perspective. Using a sample of 2,225 students (N_{7th grade} = 1,146 and N_{8th grade} = 1,079) from 16 middle schools in a city of China, we investigate the relationship between students' perceptions of their teachers’ APT, student emotions (enjoyment and anxiety) and their discursive engagement with others in the mathematics classroom. Results from structural equation modelling and mediation analysis show that after controlling for gender, family resources and mathematics achievement, student-perceived teacher APT was positively associated with their discursive engagement with classmates. Furthermore, student enjoyment and anxiety in class mediated the relationship between student-perceived teacher APT and student discursive engagement with classmates. Multi-group analysis revealed that the model was invariant across genders and grades, indicating that the associations were applicable to male and female students as well as to seventh and eighth graders. These findings shed light on the emotional relationship of teacher APT with the discursive engagement of their students. Although prior research observes a positive relationship between teacher productive classroom talk and student discursive engagement primarily through classroom observations and teacher reflections, this study provides evidence from the students’ perspective and highlights the mediating role of student emotions in the relationship.     

Does Dampened Physiological Reactivity Protect Youth in Aggressive Family Environments?

Is an attenuated physiological response to family conflict, seen in some youth exposed to early adversity, protective or problematic? A longitudinal study including 54 youth (average age 15.2 years) found that those with higher cumulative family aggression exposure showed lower cortisol output during a laboratory‐based conflict discussion with their parents, and were less likely to show the normative pattern of increased cortisol reactivity to a discussion they rated as more conflictual. Family aggression interacted with cortisol reactivity in predicting youth adjustment: Adolescents from more aggressive homes who were also more reactive to the discussion reported more posttraumatic stress symptoms and more antisocial behavior. These results suggest that attenuated reactivity may protect youth from the negative consequences associated with aggressive family environments.     

Processes of language acquisition in children with autism: evidence from preferential looking

Two language acquisition processes (comprehension preceding production of word order, the noun bias) were examined in 2- and 3-year-old children (n=10) with autistic spectrum disorder and in typically developing 21-month-olds (n=13). Intermodal preferential looking was used to assess comprehension of subject-verb-object word order and the tendency to map novel words onto objects rather than actions. Spontaneous speech samples were also collected. Results demonstrated significant comprehension of word order in both groups well before production. Moreover, children in both groups consistently showed the noun bias. Comprehension preceding production and the noun bias appear to be robust processes of language acquisition, observable in both typical and language-impaired populations.     

Coteaching in early childhood clinical field experiences: a cross-case study of learning affordances

ABSTRACT

Coteaching, a model for learning to teach, places teacher candidates alongside clinical educators in classrooms. Learning occurs through shared practice and on-going explication of thinking and reflection. This cross-case study of six dyads from an undergraduate early childhood inclusive preservice education program examines ways that coteaching afforded opportunities for developing collaborative and adaptive expertise. It was found that opportunities for learning these skills were afforded through coteaching student teaching experiences, although in different ways, and that limited affordances outnumbered strong learning opportunities. Implications for further development of the early childhood coteaching teacher education model, and for professional development, are discussed.