Development and Prediction of Context-Dependent Vowel Pronunciation in Elementary Readers

ABSTRACT

As children learn to read, they become sensitive to context-dependent vowel pronunciations in words, considered a form of statistical learning. The work of Treiman and colleagues demonstrated that readers’ vowel pronunciations depend on the consonantal context in which the vowel occurs and reading experience. Using explanatory item-response models we examined child- and nonword-factors associated with children’s assignment of more versus less frequent grapheme-phoneme correspondences (GPC) to vowel pronunciations as a function of rime coda in monosyllabic nonwords. Students (N = 96) in grades 2-5 read nonwords in which more versus less frequent vowel GPCs were wholly supported or partially favored by the rime unit. Use of less frequent vowel GPCs was predicted by set for variability, word reading, and rime support for the context-dependent vowel pronunciation. We interpret the results within a developmental word reading model in which initially incomplete and oversimplified GPC representations become more context dependent with reading experience.     

Promoting Math Talk in Adult–Child Interactions Through Grocery Store Signs

Young children have better math abilities when their parents engage in more math‐related conversations with them. Yet, previous studies have found that math talk occurs only very infrequently in everyday interactions. In the present study, we sought to promote adult–child conversations about math in a naturalistic context using minimal instructions. We observed 179 adult–child dyads while they shopped in grocery stores with signs prompting them to engage in math‐related conversations (math condition), signs prompting them to talk about other topics (general language condition), or without any signs (baseline condition). In the math condition, more adults talked about math compared to the general language or the baseline condition, and this finding could not be explained by demographic characteristics of the dyad or the overall amount of conversations. This study demonstrates that cost‐effective signs placed in everyday contexts can promote math‐related conversations and potentially provide math learning opportunities for children.     

Perceived parental stress in face of kindergarten children’s academic setback: roles of parents’ goals and education

European Journal of Psychology of Education - Previous research studies have demonstrated the link between parents’ education and parental stress level. However, these studies have not taken...     

Long-axis rotation: The missing link in proximal-to-distal segmental sequencing

Most assessments of segmental sequencing in throwing, striking or kicking have indicated a proximal-to-distal sequencing of end-point linear speeds, joint angular velocities, segment angular velocities and resultant joint moments. However, the role of long-axis rotations has not been adequately quantified and located in the proximal-to-distal sequence. The timing and importance of pronation-supination in the development of racquet head speed have been examined in the tennis serve and squash forehand drive and considered in relation to conventional concepts of proximal-to-distal sequencing. Both long-axis rotations reached their peak angular speeds late in both strokes, typically after shoulder flexion-extension, shoulder abduction-adduction and elbow extension. These results clarify and confirm the importance of upper limb long-axis rotations in the production of racquet head speed. It appears that traditional proximal-to-distal sequencing concepts are inadequate to describe accurately the complexity of the tennis serve or squash forehand drive. It is essential to consider upper arm and forearm longitudinal axis rotations in explaining the mechanics of these movements and in developing coaching emphases, strength training schedules and injury prevention programmes.     

Role of joint torques generated in an optimised Yurchenko layout vault

The purpose of the study was to quantify the muscle torques required in the performance of an optimised Yurchenko layout vault based on a five-segment rigid link model and using input data from an elite female gymnast. At impact, the wrist torque trajectory indicated an extension-flexion action while the shoulder was characterised by extension. The approximate 100 Nm (wrist flexor) and 125 Nm (shoulder extensor) respective peak torque magnitudes indicated that the impact action is not passive in nature. The contribution of joint torques to the adjoining segments was apportioned to the relative components namely; centripetal, gravity and net joint torque components. Despite the presence of both large wrist and shoulder joint torques, the net turning effect on the upper limb and hand segments about their centre of mass (CM) was small. The principal role of the upper limb joint torques was therefore to effect the appropriate joint motions and to support the weight of the gymnast. The performance of the optimum vault was primarily the result of the interplay between the centripetal and the net joint torque components at the wrist, hip and shoulder joints. This has implications to the performer in that successful execution of the vault is principally concerned with the ability to create a high angular momentum for horse impact and to then apply an appropriate level of joint torques that will make optimal use of the initial kinetic condition.     

The influence of elbow joint kinematics on wrist speed in cricket fast bowling

This modelling study sought to describe the relationships between elbow joint kinematics and wrist joint linear velocity in cricket fast bowlers, and to assess the sensitivity of wrist velocity to systematic manipulations of empirical joint kinematic profiles. A 12-camera Vicon motion analysis system operating at 250 Hz recorded the bowling actions of 12 high performance fast bowlers. Empirical elbow joint kinematic data were entered into a cricket bowling specific “Forward Kinematic Model” and then subsequently underwent fixed angle, angular offset and angle amplification manipulations. A combination of 20° flexion and 20° abduction at the elbow was shown to maximise wrist velocity within the experimental limits. An increased elbow flexion offset manipulation elicited an increase in wrist velocity. Amplification of elbow joint flexion–extension angular displacement indicated that, contrary to previous research, elbow extension range of motion and angular velocity at the time of ball release were negatively related to wrist velocity. Some relationships between manipulated joint angular waveforms and wrist velocity were non-linear, supporting the use of a model that accounts for the non-linear relationships between execution and outcome variables in assessing the relationships between elbow joint kinematics and wrist joint velocity in cricket fast bowlers.     

The effect of altered pitch length on performance and technique in junior fast bowlers

The aim of this study was to assess the effect of pitch length (20.12 m [full length], 18 m and 16 m) on the fast bowling performance and technique of junior cricketers. Performance measures included ball release speed and accuracy, while technique variables evaluated were those shown to be related to the aetiology of lower back injury. Thirty-seven fast bowlers from the under-11 (n=14), under-13 (n=11) and under-15 (n=12) age groups were filmed bowling five deliveries at each of the above pitch lengths. Two synchronized NAC video cameras operating at 200 Hz permitted three-dimensional reconstruction of the hip and shoulder alignments, while a standard digital video camera operating at 50 Hz (positioned perpendicular to the bowling action) was used to measure front knee angle and ball release speed. Accuracy scores were taken from a zoned target at the batsman's stumps. A two-way analysis of variance with repeated measures (with age and pitch length as the between- and within-participant variables, respectively) was used to compare each age group at the 0.05 significance level. Results showed that accuracy improved in all age groups at shorter pitch lengths, although ball velocity remained constant throughout all trials. Shoulder counter-rotation increased significantly for the under-13 bowlers when bowling on the full-length pitch in comparison with the two shorter lengths. Counter-rotation also increased on the full-length pitch in the under-11 age group, although this increase was not significant. The under-15 bowlers' techniques did not change as pitch length increased. As under-11 and under-13 bowlers adopted a "safer" bowling action with superior accuracy on the 18?m compared with the full length pitch, it was concluded that these age groups should bowl on an 18?m pitch to reduce the likelihood of lower back injuries and improve accuracy.     

Development of a computer-assisted cranial nerve simulation from the visible human dataset

Advancements in technology and personal computing have allowed for the development of novel teaching modalities such as online web‐based modules. These modules are currently being incorporated into medical curricula and, in some paradigms, have been shown to be superior to classroom instruction. We believe that these modules have the potential of significantly enriching anatomy education by helping students better appreciate spatial relationships, especially in areas of the body with greater anatomical complexity. Our objective was to develop an online module designed to teach the anatomy and function of the cranial nerves. A three‐dimensional model of the skull, brainstem, and thalamus were reconstructed using data from the Visible Human Project and Amira®. The paths of the cranial nerves were overlaid onto this 3D reconstruction. Videos depicting these paths were then rendered using a “roller coaster‐styled” camera approach. Interactive elements adding textual information and user control were inserted into the video using Adobe Creative Suite® 4, and finally, the module was exported as an Adobe Flash movie to be viewable on Internet browsers. Fourteen Flash‐based modules were created in total. The primary user interface comprises a website encoded in HTML/CSS and contains links to each of the 14 Flash modules as well as a user tutorial. Anat Sci Educ 4: 92–97, 2011. © 2010 American Association of Anatomists.