Exploring the Complexity of Students’ Scientific Explanations and Associated Nature of Science Views Within a Place-Based Socioscientific Issue Context

Science & Education - In addition to considering sociocultural, political, economic, and ethical factors (to name a few), effectively engaging socioscientific issues (SSI) requires that...     

Leg mass characteristics of accurate and inaccurate kickers – an Australian football perspective

Abstract

Athletic profiling provides valuable information to sport scientists, assisting in the optimal design of strength and conditioning programmes. Understanding the influence these physical characteristics may have on the generation of kicking accuracy is advantageous. The aim of this study was to profile and compare the lower limb mass characteristics of accurate and inaccurate Australian footballers. Thirty-one players were recruited from the Western Australian Football League to perform ten drop punt kicks over 20 metres to a player target. Players were separated into accurate (n = 15) and inaccurate (n = 16) groups, with leg mass characteristics assessed using whole body dual energy x-ray absorptiometry (DXA) scans. Accurate kickers demonstrated significantly greater relative lean mass (P ≤ 0.004) and significantly lower relative fat mass (P ≤ 0.024) across all segments of the kicking and support limbs, while also exhibiting significantly higher intra-limb lean-to-fat mass ratios for all segments across both limbs (P ≤ 0.009). Inaccurate kickers also produced significantly larger asymmetries between limbs than accurate kickers (P ≤ 0.028), showing considerably lower lean mass in their support leg. These results illustrate a difference in leg mass characteristics between accurate and inaccurate kickers, highlighting the potential influence these may have on technical proficiency of the drop punt.     

Analyzing the teaching of advanced mathematics courses via the enacted example space

Examples are believed to be very important in developing conceptual understanding of mathematical ideas, useful both in mathematics research and instruction (Bills & Watson in Educational Studies in Mathematics 69:77–79, 2008; Mason & Watson, 2008; Bills & Tall, 1998; Tall & Vinner, 1981). In this study, we draw on the concept of an example space (Mason & Watson, 2008) and variation theory (Runesson in Scandinavian Journal of Educational Research 50:397–410, 2006) to create a lens to study how examples are used for pedagogical purposes in undergraduate proof-based instruction. We adapted the construct of an example space and extended its application to the constructs of example neighborhood, methods of example construction, and the functions of examples. We explained how to use our new lens to analyze the collection of examples and non-examples that the students had access to. We then demonstrate our method by analyzing the collection of examples and non-examples of a mathematical group the professor of an abstract algebra class presented during lectures or assigned to students in problem sets or exams.     

Fractions: Could they really be the gatekeeper’s doorman?

The National Mathematics Advisory Panel (NMAP, 2008) asserts that a foundational knowledge of fractions is crucial for students’ success in algebra; however, empirical evidence for this claim is relatively nonexistent. In the present study, we examine the impact of middle school students’ fraction and whole number magnitude knowledge on various components of their algebra readiness. Results suggest that fraction knowledge is related to algebra readiness, more so than number magnitude knowledge in general; students’ magnitude knowledge of unit fractions (i.e., those with a numerator of 1) appears particularly important. Findings confirm the intuition of the NMAP (2008) and support the recommendation of the Common Core Standards (National Governors Association Center for Best Practices (NGA Center), 2010) that students’ fraction knowledge should be cultivated using number lines.     

Wrestling

The purpose of this study was to determine whether there is a significant difference in the co‐efficient of friction (Fc) between old versus new wrestling shoes and mats and to investigate the effect of perspiration. Fc was measured by dragging a weighted shoe over a wrestling mat surface and measuring the vertical and horizontal forces produced. Three different shoe conditions were assessed over two mat types for both wet and dry conditions for a total of 12 conditions. To simulate the wet condition, saline solution was smeared over the surface of the mat. There was a significant effect of shoe, mat, and wet/dry conditions. In addition, significant interactions of shoe by mat, shoe by dry/wet, and mat by dry/wet were observed. Overall, Fc was 36% higher for the new wrestling mat compared to the old wrestling mat. Application of the saline solution reduced Fc by 14% compared to the dry condition. Comparison of the mean Fc for all three shoe types revealed the Fc for the older design shoe was 23% to 28% lower than the brand new shoe and the worn newer design, respectively. A high Fc, such as in the new mat/new shoe combination, has the potential to increase the risk of knee and ankle injuries by fixing the foot more securely to the ground.     

The impact of structural salience within on‐air promotion

To determine what maximizes the effectiveness of on‐air promotions, as measured by ratings/share changes, this study tested a seven‐part model focusing on the structural salience of network prime‐time promos carried within other prime‐time programs. The results of analysis of more than 5,000 promos carried within 656 videotaped prime‐time hours provided consistent support for the salience model. Results showed significant changes in industry promotional practices over time and significant differences by network, genre, and the familiarity of the program to audiences. Although lead‐in ratings remained the dominant force impacting ratings for series programs (but not sporting events, movies, or specials), promotional salience variables contributed significantly to improved ratings, especially for mid‐rated continuing programs.     

互补性与次协调性

玻尔互补性原理的准确意义已引起了许多争论。这里我们并不打算对玻尔的观点进行详细的评论,而是对在一种明确的意义上包含互补性被我们称之为C-理论的理论所能理解的东西作尽可能有道理的解释。那些理论的基本逻辑是一种通过对经典逻辑的演绎概念作恰当修改而得到的所谓＂次经典＂逻辑。粗略地说,C-理论是含有＂物理上＂不相容定理（尤其是矛盾定理）的非平庸理论。因此,其基本逻辑是一种次协调逻辑。本文被视为我们有关C-理论及其应用的一系列作品的第一篇。     

Developing indicators of classroom practice to evaluate the impact of district mathematics reform initiative: A generalizability analysis

This paper reported results from a generalizability study that examined the process of developing classroom practice indicators used to evaluate the impact of a school district's mathematics reform initiative. The study utilized classroom observational data from 32 second, fourth, eighth, and tenth grade teachers. The study addresses important measurement issues in developing classroom practice indicators used as evaluation outcome measures. This study also demonstrates that the G-theory measurement framework has important applications in practice-oriented settings. Namely, the use of G-theory provides insights into the tradeoffs between number of observations and number of raters when using observational data to conduct evaluation. The use of decision analysis provided a procedure for forecasting the optimum mix of the two for each situation.