Energy balance of locomotion with pedal-driven watercraft

Abstract

In this study, we examined the mechanics and energetics of locomotion with a paddle-wheel boat and a water bike. Power output ([Wdot] _tot) was measured directly on the water bike by means of an instrumented chain-ring. The simultaneous assessment of oxygen uptake ([Vdot]O₂) allowed the computation of the “overall” efficiency of locomotion (η _o = [Wdot] _tot / [Vdot]O₂). Mean η _o was 0.27 (s = 0.02), which was unaffected by the speed, and was assumed to be the same for the two boats as both are semi-recumbent bicycles. For the paddle-wheel boat, [Wdot] _tot was then obtained from η _o and measures of [Vdot]O₂. The power to overcome (passive) drag was calculated as [Wdot] _d = D · v (where D is the force measured by means of a load cell when towing the boats at given speeds). Propelling efficiency was calculated as η _p = [Wdot] _d / [Wdot] _tot, which was lower with the paddle-wheel boat (mean 0.35, s = 0.01) than with the water bike (mean 0.57, s = 0.01). The observed differences in η _p and [Wdot] _d explain why at the highest speed tested (～3 m · s^?1), the energy required to cover a unit distance with the water bike is similar to that required to move the paddle-wheel boat at 1.3 m · s^?1.     

Sensitive periods in the development of attachment and the age of entry into day care

This study investigated how the age of entry into regular group day care may influence, in the context of other relevant variables, some short-time outcomes of this experience. In particular the study focused on behaviours expressing well-being or discomfort in the day care environment during the third year. Subjects were 129 young children who were enrolled in group day care when they were 6–29 months old. During their third year their social behaviour was evaluated by caregivers with the Day Care Adaptation Scale. Researchers observed 54 of the children in reunion with their parents. The quality of care was rated with the ITERS scale. It was found that children who started day care in the intervals 6–12 months and 18–23 months displayed more frequently difficult reunions with their mothers, and were rated as less resistant to frustration. Children who started day care from 12–17 months showed lower relational distress. Some significant relationships were found between the ratings of ITERS and the Day Care Adaptation Scale. These findings are discussed with reference to theories of attachment.     

From childhood nature experiences to adult pro-environmental behaviors: An explanatory model of sustainable food consumption

Abstract

In two studies, the role of nature experiences and social norms during childhood is explored next to adulthood biospheric values, connectedness to nature, environmental identity, and objective knowledge in relation to pro-environmental behaviors. Study 1 (N?=?185) tested the hypothesized model in the realm of general pro-environmental behaviors and sustainable fruit consumption on a sample of students. Study 2 (N?=?155) tested the model in the realm of sustainable seafood consumer choice on a general population sample. Path analyses show consistent results across samples. Results show that childhood nature experiences and exposure to pro-environmental social norms during childhood are related to adulthood development of connectedness with nature and biospheric values; these, in turn, help in shaping adulthood environmental self-identity ultimately influencing the enactment of sustainable food choices during adulthood. These findings point toward the relevance of childhood experiences for pro-environmental behaviors as compared to the provision of information. The role of objective knowledge across samples is inconsistent, thus requiring future investigations.     

Contributions of Academic Language,Perspective Taking,and Complex Reasoning to Deep Reading Comprehension

ABSTRACT

Deep reading comprehension refers to the process required to succeed at tasks defined by the Common Core State Literacy Standards, as well as to achieve proficiency on the more challenging reading tasks in the Program for International Student Assessment (PISA) framework. The purpose of this study was to test the hypothesis that three skill domains not frequently attended to in instruction or in theories of reading comprehension—academic language, perspective taking, and complex reasoning—predict outcomes on an assessment of deep reading comprehension. The Global Integrated Scenario-based Assessment (GISA; O'Reilly, Weeks, Sabatini, Halderman, & Steinberg, 2014 O'Reilly T., Weeks, J., Sabatini, J., Halderman, L., & Steinberg, J. (2014). Designing reading comprehension assessments for reading interventions: How a theoretically motivated assessment can serve as an outcome measure. Educational Psychology Review, 26, 403–424. doi:10.1007/s10648-014-9269-z[Crossref], [Web of Science ®] , [Google Scholar]) is designed to reflect students' abilities to evaluate texts, integrate information from an array of texts, and use textual evidence to formulate a position, all features of deep reading comprehension. We tested the role of academic language, perspective taking, and complex reasoning in explaining variance in end-of-year GISA scores, controlling for beginning-of-year scores and student demographics. All three predictors explained small, but significant, amounts of additional variance. We suggest that these three skill domains deserve greater attention in theories of reading comprehension and in instruction.     

Self-rated wellbeing and physical activity associations in European older adults

Background: Physical activity and self-rated wellbeing have important benefits to health. However, scientific knowledge regarding their relationship among older adults is scarce. Thus, the aim of this study was to examine the associations between physical activity frequency and several dimensions of self-rated wellbeing, in a representative sample of European older adults from 28 countries. Methods: This study is based on the European Social Survey round 6, 2012. It had a total sample size of 12,341 older adults (5100 men, 7241 women) with mean age 73.8?±?6.6 years. Information was collected through a questionnaire, filled-in during an hour-long face-to-face interview. Physical activity was accessed using the question “On how many of the last 7 days you were physically active continuously for 20 minutes or longer?” and six dimensions of self-rated wellbeing were used. Results: Physical activity in the last 7 days was linearly related with all dimension of the self-rated wellbeing and with wellbeing total score for both sexes (men, β?=?0.09, 95% CI: 0.07 to 0.10, p?β?=?0.10, 95% CI: 0.09 to 0.11, p?Conclusions: Physical activity promotion should be stressed as a meaningful strategy to improve people's wellbeing overall. This strategy has special importance when considering the older adult population.     

Verifying the operation of an elastic crossbar system applied to a panel painting: the Deposition from the Cross by an anonymous artist from Abruzzo,sixteenth century

This study deals with the post-treatment evaluation of the elastic crossbar system already designed and installed on the recently restored panel painting Deposition from the Cross by an anonymous artist from Abruzzo (sixteenth century). After the restoration, the panel and the crossbars were subjected to mechanical tests to identify their elastic characteristics. Then the panel, equipped with the elastic crossbar system, was subjected for about two months to controlled environmental cycles made up of approximately constant humidity periods. During the two months, the forces exerted by the springs and the deformations of both panel and crossbars were continuously monitored. A mathematical model, calibrated on the specific parameters derived from the analysis of the panel, provided the deformation that the panel would have shown without the crossbars; comparing the model output with the measured data provided a restraining effect (RE) of approximately 7% (RE could range between zero – no restraint – and 100% – total restraint). Future developments of this project will define appropriate procedures to design an elastic crossbar system for a given panel, once the expert judgement of restorers has identified the most desirable RE to be achieved.     

Making knowledge visible: Using expert yellow pages to map capabilities in professional services firms

Professional services firms survive by exploiting the skills and knowledge of their employees to deliver a range of projects for clients. As a result of working on these projects, an organization's capabilities evolve in unpredictable and often divergent ways. In order to help their staff conduct these projects, services firms have invested heavily in knowledge management systems. To date, few attempts have been made to use the information contained in these knowledge management systems to understand the nature and evolution of capabilities in professional services firms. Using the expert yellow pages of Arup, one of the world's leading engineering consultancies, we develop a new approach based on co-word and proximity analysis to map the knowledge and skills of professional services firms. This approach provides a mechanism to allow such firms to better understand what they know and help them to deploy their skills in new and potentially lucrative ways.     

Retention and persistence of African‐American students in school psychology programs

This qualitative study investigated eight African‐American specialist‐level students’ experiences with and perceptions of their retention and persistence toward degree completion in school psychology programs. Findings indicate that participants deemed the general supports faculty offered to all students and positive, supportive relationships with faculty as retention strategies they experienced as effective and access to diversity in support systems as a retention strategy they perceived would be beneficial. Participants described social engagement and reliance on family and classmates as persistence strategies they used. Based on these findings, the article provides recommendations for school psychology faculty interested in retaining African‐American students and African‐American students who aim to persist to degree completion.     

Whither social theory?

What is the place of social theory in mathematics education research, and what is it for? This special issue of Educational Studies in Mathematics offers insights on what could be the role of some sociological theories in a field that has historically privileged learning theories coming from psychology and mathematics as the main theoretical frames informing research. Although during the last 10 years the term “socio-cultural” has become part of the accepted and widespread trends of mathematics education research when addressing learning, this issue gathers a collection of papers that depart from a “socio-cultural” approach to learning and rather deploy sociological theories in the analysis of mathematics education practices. In this commentary paper, we will point to what we see to be the contributions of these papers to the field. We will do so by highlighting issues that run through the six papers. We will try to synthetize what we think are the benchmarks of the social approach to mathematics education that they propose. We will also take a critical stance and indicate some possible extensions of the use of social theory that are not addressed in this special issue but nonetheless are worth being explored for a fuller understanding of the “social” in mathematics education.