Effect on development of proportional reasoning skill of physical experience and cognitive abilities associated with prefrontal lobe activity

The present study tested the hypothesis that maturing prefrontal lobes play a role in the development of proportional reasoning skill because the prefrontal lobes are involved in the inhibition of task‐irrelevant information and the representation of task‐relevant information. The hypothesis that reasoning development is in part dependent upon physical experience was also tested. Students (all males) who failed to solve a diagnostic proportions task were administered several tests of prefrontal lobe functions. The students were then randomly assigned to manipulative or verbal tutoring groups. Both groups received a series of individual testing, tutoring and testing sessions on proportional reasoning. As predicted, performance on the prefrontal lobe tasks (measures of inhibiting ability, planning ability, dissembedding ability, and working memory capacity) significantly predicted performance on proportional reasoning tasks following tutoring. Students' computational skills were not a significant predictor. Also, the manipulative group's proportional reasoning performance was significantly higher than that of the verbal tutoring group. Therefore, the present results provide support for the hypothesis that maturing prefrontal lobes and physical experience play roles in the development of proportional reasoning skill. © 2000 John Wiley & Sons, Inc. J Res Sci Teach 37: 1171–1182, 2000     

Hong Kong Student Teachers' Personal Construction Of Teaching Efficacy

This study employed the repertory grid technique to investigate how a sample of 27 student teachers in Hong Kong developed a personal sense of teaching efficacy. The analysis indicated that the third year students' perceptions were more homogenous than were those of the first year students. The results also indicated that teaching efficacy was viewed in terms of the dimensions of concern for instructional participation and learning needs of pupils, communication and relationships with pupils, academic knowledge and teaching skills, lesson preparation, management of class discipline, teaching success, teaching commitment, and a sense of self-confidence. Experiences of teaching practice, electives, pupils, and teaching practice supervisors (Electives) were the major sources for the development of a sense of teaching efficacy. Implications of how those aspects of teacher training can be more effective in engendering a sense of efficacy in the student teachers are discussed.     

A microfluidic platform for studying the effects of small temperature gradients in an incubator environment

Studies on the effects of variations in temperature and mild temperature gradients on cells, gels, and scaffolds are important from the viewpoint of biological function. Small differences in temperature are known to elicit significant variations in cell behavior and individual protein reactivity. For the study of thermal effects and gradients in vitro, it is important to develop microfluidic platforms which are capable of controlling temperature gradients in an environment which mimics the range of physiological conditions. In the present paper, such a microfluidic thermal gradient system (μTGS) system is proposed which can create and maintain a thermal gradient throughout a cell-seeded gel matrix using the hot and cold water supply integrated in the system in the form of a countercurrent heat exchanger. It is found that a uniform temperature gradient can be created and maintained in the device even inside a high temperature and high humidity environment of an incubator. With the help of a hot and cold circuit controlled from outside the incubator the temperature gradient can be regulated. A numerical simulation of the device demonstrates the thermal feature of the chip. Cell viability and activity under a thermal gradient are examined by placing human breast cancer cells in the device.     

Variable‐Length Computerized Adaptive Testing Using the Higher Order DINA Model

Cognitive diagnosis models provide profile information about a set of latent binary attributes, whereas item response models yield a summary report on a latent continuous trait. To utilize the advantages of both models, higher order cognitive diagnosis models were developed in which information about both latent binary attributes and latent continuous traits is available. To facilitate the utility of cognitive diagnosis models, corresponding computerized adaptive testing (CAT) algorithms were developed. Most of them adopt the fixed‐length rule to terminate CAT and are limited to ordinary cognitive diagnosis models. In this study, the higher order deterministic‐input, noisy‐and‐gate (DINA) model was used as an example, and three criteria based on the minimum‐precision termination rule were implemented: one for the latent class, one for the latent trait, and the other for both. The simulation results demonstrated that all of the termination criteria were successful when items were selected according to the Kullback‐Leibler information and the posterior‐weighted Kullback‐Leibler information, and the minimum‐precision rule outperformed the fixed‐length rule with a similar test length in recovering the latent attributes and the latent trait.     

Academic Self-Concepts in Ability Streams: Considering Domain Specificity and Same-Stream Peers

The study examined the relations between academic achievement and self-concepts in a sample of 1,067 seventh-grade students from 3 core ability streams in Singapore secondary education. Although between-stream differences in achievement were large, between-stream differences in academic self-concepts were negligible. Within each stream, levels of students’ achievement and their self-concepts were systematically related only when considered in the matching academic domain and the appropriate level of specificity. In English, lower achievers in the high-ability stream tended to underestimate their achievement, whereas higher achievers in the low-ability stream tended to overestimate their achievement. This pattern, however, was not evident in mathematics and the general academic domain. Taken together, the findings highlight the importance of considering the interplay of domain specificity and same-stream peers in academic self-concepts.     

The Use of Think-Aloud to Evaluate a Navigation Structure for a Multimedia Health and Wellness Application for Older Adults and Their Caregivers

Despite the increasing use of health information technologies (HITs) for older adults living in the community and their caregivers, few have been rigorously evaluated for usability by the end users. Think-aloud protocols are a relatively easy method for both clinicians and researchers to use with older adults and those therapists that work with them to provide such an evaluation. In the present report, we provide an exemplar using this method in order to evaluate the usability of a health and wellness technology tool designed for older adults and caregivers. In addition, we discuss methodological and practical considerations for others interested in this approach. The methodology described in this study is easy and practical to undertake, and it can be effectively conducted by researchers and clinicians to find usability issues related to HITs for older adults and their caregivers.