Generalized loxodromes with application to time-optimal navigation in arbitrary wind

This article aims at generalizing loxodromic (rhumb line) navigation to conformally flat Riemannian manifolds. We admit space-time dependence of both perturbing vector field and ship’s self-speed. Thereafter, the findings are applied to time-efficient navigation by a variational approach, referring to the local solutions of Zermelo’s navigation problem under arbitrary wind. This yields the corresponding conditions for loxodromic time-minimal and time-maximal navigation in relation to the navigation data. Our research is also illustrated by a two-dimensional example (an oblate ellipsoid), which distinguishes perturbations of different force: weak, critical and strong. It includes numerical simulations and discussion, emphasizing and comparing loxodromic solutions among the minimizing, maximizing and anomalous time extremals.     

Seasonal variation in physical activity among preschool children in a northern Canadian city

Little research has examined seasonal differences in physical activity (PA) levels among children. Proxy reports of PA were completed by 1,715 parents on their children in Edmonton, Alberta, Canada. Total PA (TPA) minutes were calculated, and each participant was classified as active, somewhat active, or inactive. Logistic regression models were conducted to examine associations between PA status and seasons. Significant seasonal differences were observed for TPA, weekday PA, weekend PA, and active play. Children were significantly more likely to be physically active in the summer and spring and somewhat physically active in the summer and fall, relative to winter Children living in cold climates are less likely to be physically active in the winter.     

Perturbations in Blood Phosphatidylcholine and Sphingomyelin Fatty Acid Composition in a Sample Population of Cigarette Smokers

Docosahexaenoic (DHA) and arachidonic acids (AA) are polyunsaturated fatty acids (PUFAs), major components of brain tissue and neural systems, and the precursors of a number of biologically active metabolites with functions in inflammation resolution, neuroprotection and other actions. As PUFAs are highly susceptible to peroxidation, we hypothesised whether cigarette smokers would present altered PUFAs levels in plasma and erythrocyte phospholipids. Adult males from Indian, Sri-Lankan or Bangladeshi genetic backgrounds who reported smoking between 20 and 60 cigarettes per week were recruited. The control group consisted of matched non-smokers. A blood sample was taken, plasma and erythrocyte total lipids were extracted, phospholipids were separated by thin layer chromatography, and the fatty acid content analysed by gas chromatography. In smokers, dihomo-gamma-linolenic acid, the AA precursor, was significantly reduced in plasma and erythrocyte phosphatidylcholine. AA and DHA were significantly reduced in erythrocyte sphingomyelin. Relatively short term smoking has affected the fatty acid composition of plasma and erythrocyte phospholipids with functions in neural tissue composition, cell signalling, cell growth, intracellular trafficking, neuroprotection and inflammation, in a relatively young population. As lipid peroxidation is pivotal in the pathogenesis of atherosclerosis and neurodegenerative diseases such as Alzheimer disease, early effects of smoking may be relevant for the development of such conditions.     

Seasonal Variation in Physical Activity Among Preschool Children in a Northern Canadian City

Little research has examined seasonal differences in physical activity (PA) levels among children. Proxy reports of PA were completed by 1,715 parents on their children in Edmonton, Alberta, Canada. Total PA (TPA) minutes were calculated, and each participant was classified as active, somewhat active, or inactive. Logistic regression models were conducted to examine associations between PA status and seasons. Significant seasonal differences were observed for TPA, weekday PA, weekend PA, and active play. Children were significantly more likely to be physically active in the summer and spring and somewhat physically active in the summer and fall, relative to winter. Children living in cold climates are less likely to be physically active in the winter     

Evaluation of engineering and technology activities in primary schools in terms of learning environment,attitudes and understanding

Because the importance of science, technology, engineering and mathematics (STEM) education continues to be recognised around the world, we developed and validated an instrument to assess the learning environment and student attitudes in STEM classrooms, with a specific focus on engineering and technology (E&T) activities in primary schools. When a four-scale instrument assessing classroom cooperation and involvement and student enjoyment and career interest was administered to 1095 grade 4–7 students in 36 classes in 10 schools, data analyses supported its factorial validity and reliability. When the new questionnaire and understanding scales were used to evaluate E&T activities, statistically-significant pretest–posttest changes in career interest and understanding (with large effect sizes ranging from 0.70 to 0.81 standard deviations) supported the efficacy of the instructional activities.     

A brief history of family life education in Romania

Starting from the state of conceptual diversity, semantic ambiguity, and poor connection of family life education practices to current policies and theoretical models in Romania, our study aims at understanding the underlying meanings of these issues by recourse to the history of approaches in the field. To this purpose, we carried out a qualitative historical research, based on the thematic analysis of a set of educational works produced between the sixteenth century, when the first Romanian texts were written, and the present time. Primary historical sources are supplemented with reliable secondary sources, while the criteria used for the selection of texts were their relevance to family life education (FLE), and the notoriety of the works in the corresponding historical periods. As in western countries, the concept of FLE was coined in Romania at the beginning of the twentieth century, when the family education discourse was outlined, but the roots of the field can be traced even in the first printed texts. Although marked by strong moral and religious emphases during pre-modernity, FLE has entered the slow process of secularisation and evolved from the perspective of political, social, and moral reconstruction goals of modern Romania. However, FLE’s goals and contents were redefined during Communism, and the discrepancies between discourses, practices, and realities compromised the functionality of the pedagogical model promoted at the time. A unitary definition of FLE in relation to Romanian contemporary families’ needs requires reconciliation with historical, cultural, and educational premises, as well as a careful contextualisation of western models and practices.     

Makerspace in STEM for girls: a physical space to develop twenty-first-century skills

Makerspace has been lauded as a new way forward to create communities, empower students and bring together enthusiasts of all ages and skill levels “to tinker” and create. Makerspace education has been touted as having the potential to empower young people to become agents of change in their communities. This paper examines how a Makerspace approach can capture the imagination and creativity of female primary school students, and engage them in integrated STEM-based projects. The study scaffolded female tertiary undergraduate students to mentor small groups of girls to complete a project in a STEM Makerspace situated in classrooms. The data generated and analysed from this study were used to determine how Makerspace STEM-based projects were enacted, how they engaged and supported the girls’ learning, and considers the future of a Makerspace approach as a way to progress integrated STEM education.     

Educating and Measuring Choice: A Test of the Transfer of Design Thinking in Problem Solving and Learning

Educators aim to equip students with learning strategies they can apply when approaching new problems on their own. Teaching design-thinking strategies may support this goal. A first test would show that the strategies are good for learning and that students spontaneously transfer them beyond classroom instruction. To examine this, we introduce choice-based assessments (CBAs). CBAs measure how people learn when there is minimal guidance and they must make decisions as independent learners. Here, sixth-grade students completed multiple design activities that emphasized either seeking constructive criticism or exploring a space of alternatives. Afterward, they completed the CBAs, which measured strategy transfer. Results showed that lower-achieving students benefitted most from instruction, exhibiting a relative increase in their use of design-thinking strategies. In addition, strategy choices correlated with prior achievement measures and appeared to mediate performance in and learning from the CBAs. The choices to use the two strategies themselves were not correlated, which indicates that they are not subsets of a larger construct, such as growth mindset. In sum, CBAs enabled a double demonstration: design-thinking strategies may improve learning and problem solving, and design-thinking instruction may improve the likelihood of lower-achieving students choosing to use effective strategies in novel settings that require new learning.     

A digital game-based assessment of middle-school and college students’ choices to seek critical feedback and to revise

A major goal of contemporary education is to teach students how to learn on their own. Assessments have largely lagged behind this goal, because they measure what students have learned and not necessarily their learning processes. This research presents Posterlet, an assessment that collects evidence regarding the strategies that students choose while learning on their own. Posterlet is an educational game-based assessment that measures two design thinking choices: students’ choices to seek critical (ie, negative) feedback and to revise their work while they learn graphic design principles through creating posters. This research also presents an examination of students’ choices to seek feedback and to revise, as well as of students’ learning outcomes based on these choices. This game-based assessment approach is empirically validated with three research studies sampling nearly 300 middle-school and college students who played Posterlet and completed a posttest. Results show that the game helps students learn, as students who play the game before completing the posttest learn more graphic design principles than students who only complete the posttest. Moreover, the choices to seek critical feedback and to revise can predict learning and can be used as valid outcome measures for learning. Findings can be used in developing and evaluating models of instruction and assessment that may help students make informed learning choices. A discussion of present and future trends in theory regarding digital feedback environments is also included.