Embryonic auditory experience and maternal call recognition

Peking duck embryos respond selectively to the maternal call of their species on the day before hatching, given normal embryonic auditory experience (the sounds emanating from their siblings and themselves which begin late on Day 24 of development). Groups of Peking embryos were subjected to recordings of either the mallard or the Burmese red jungle fowl maternal call beginning on Day 21 of incubation. Responses to these calls were tested on the day before hatching to determine the effects of the prenatal auditory experience. The responses of those birds exposed to the mallard maternal call were neither attenuated nor enhanced (as compared to the controls) when presented that call; those subjects which were exposed to the jungle fowl maternal call later failed to respond to that call or the mallard maternal call.     

Enhanced handling and positioning in early infancy advances development throughout the first year

Behaviors emerge, in part, from the interplay of infant abilities and caregiver–infant interactions. Cross‐cultural and developmental studies suggest caregiver handling and positioning influence infant development. In this prospective, longitudinal study, the effects of 3 weeks of enhanced handling and positioning experiences provided to 14 infants versus control experiences provided to 14 infants at 2 months of age were assessed with follow‐up through 15 months of age. Behaviors in prone were immediately advanced. Short‐term advancements occurred in multiple behaviors, including prone, head control, reaching, and sitting behaviors. Longer term advancements, up to 12 months after the experience period, occurred in object transfer, crawling and walking behaviors. This suggests broad and long‐lasting changes can arise via brief periods of change in caregiver–infant interactions.     

Optimal pruning for tree-structured vector quantization

Tree-structured vector quantization (VQ) is a technique designed to represent a codebook that simplifies encoding as well as vector quantizer design. Most design algorithms for tree-structured VQ used in the past are based on heuristics that successively partition the input space. Recently, Chou, Lookabaugh and Gray proposed a tree-pruning heuristic in which a given initial tree is pruned backwards according to certain optimization criterion. We define the notion of an optimal pruned tree subject to a cost constraint and study the computational complexity of finding such an optimal tree for various cost functions. Under the assumption that all trees are equally probable, we show that, on the average, the number of pruned trees in a given tree is exponential in the number of leaves. Furthermore, we prove that finding an optimal pruned tree subject to constraints such as entropy or the expected-depth is NP-hard. However, we show that when the constraint is the number of leaves, the problem can be solved in polynomial time. We develop an algorithm to find the optimal pruned tree in O(nk) time, where n is the size of the initial tree and kis the constraint size.     

An evaluation of inertial sensor technology in the discrimination of human gait

Abstract

Inertial sensors may provide the opportunity for broader and more cost effective gait analysis; however some questions remain over their potential use in this capacity. The aim of the study was to determine whether an inertial sensor could discriminate between normal walking, fast walking, and running. A single group crossover design was used to compare acceleration profiles between three gait conditions: normal walking, fast walking, and running. An inertial sensor was placed on the sacrum of 12 participants (6 male, 6 female) who performed 3 trials of each gait condition on both overground and treadmill settings. A significant difference (P < 0.001) in the occurrence of heel strike in the gait cycle was found between running and both walking conditions. No differences were seen between overground and treadmill in any condition or variable. The results indicate that a single sacral mounted inertial sensor can differentiate running from normal walking and fast walking using temporal gait event measures. This study indicates that inertial sensors can differentiate walking from running gait in healthy individuals which may have potential for application in the quantification of physical activity in the health and exercise industry.     

Bias among Professionals Who Erroneously Declare Students Eligible for Special Services

A computer simulation program was developed for the purpose of studying the processes diagnostic personnel in the schools engage in when making psychoeducational decisions about students. Initially, the program collected demographic data on 159 participants and assessed their knowledge base in assessment. Bogus referral information for one of sixteen “cases” was then provided and subjects were instructed that they were to make eligibility and classification decisions for the child. They were told that scores and other information (e.g., observations) were available to them on a variety of tests from among seven domains. Although the referral data indicated the student might be evidencing academic or behavior problems, all assessment data indicated a normal or average performance. Fiftytwo percent of the subjects (i.e., 83) declared the “average” child eligible for special education services; their classification decisions were further analyzed. Decisions about the 16 different children were found to be more a function of referral information than child performance data. The outcomes are discussed with regard to implications for the practice of psychoeducational assessment.     

Historical Frameworks and Sporting Research

Abstract

In recent years, there has been a wealth of research into how the game of association football developed. However, rather than establishing a common theme this research has led to competing theories with the debate dividing opinion on how the game of football was developed and propagated. While debate is healthy, the approach taken by some could lead to fellow academics looking to those engaged in sport history as unprofessional. This paper seeks to propose a way forward with academics working towards an all-encompassing history of the sport, by suggesting the adoption of a framework based on the work of Fernand Braudel, where indepth analysis of individual events is combined with the identification of transformational cycles. The paper concludes by suggesting that historians interested in soccer’s early history work together within the framework to develop a more detailed and all-encompassing early history of the sport. This framework will not claim that either the orthodox or revisionist view is accurate, instead it will determine how best to work those debates into an all-encompassing approach while searching for detailed evidence on what was actually occurring at local levels.     

Effects of curricular activity on students' situational motivation and physical activity levels

The purpose of this study was to examine (a) the effects of three curricular activities on students'situational motivation (intrinsic motivation [IM], identified regulation [IR], external regulation, and amotivation [AM]) and physical activity (PA) levels, and (b) the predictive strength of situational motivation to PA levels. Four hundred twelve students in grades 7-9 participated in three activities (cardiovascular fitness, ultimate football, and Dance Dance Revolution [DDR]) in physical education. ActiGraph GT1M accelerometers were used to measure students' PA levels for three classes for each activity. Students also completed a Situational Motivation Scale (Guay, Vallerand, & Blanchard, 2000) at the end of each class. Multivariate analysis of variance revealed that students spent significantly higher percentages of time in moderate-to-vigorous PA (MVPA) in fitness and football classes than they did in DDR class. Students reported higher lM and IR toward fitness than DDR They also scored higher in IR toward fitness than football. In contrast, students displayed significantly lower AM toward fitness than football and DDR Hierarchical Linear Modeling revealed that IM was the only positive predictor for time in MVPA (p = .02), whereas AM was the negative predictor (p < .01). The findings are discussed in regard to the implications for educational practice.