A novel on-chip three-dimensional micromachined calorimeter with fully enclosed and suspended thin-film chamber for thermal characterization of liquid samples

A microfabricated calorimeter (μ-calorimeter) with an enclosed reaction chamber is presented. The 3D micromachined reaction chamber is capable of analyzing liquid samples with volume of 200 nl. The thin film low-stress silicon nitride membrane is used to reduce thermal mass of the calorimeter and increase the sensitivity of system. The μ-calorimeter has been designed to perform DC and AC calorimetry, thermal wave analysis, and differential scanning calorimetry. The μ-calorimeter fabricated with an integrated heater and a temperature sensor on opposite sides of the reaction chamber allows to perform thermal diffusivity and specific heat measurements on liquid samples with same device. Measurement results for diffusivity and heat capacitance using time delay method and thermal wave analysis are presented.     

Toward better research on child abuse and neglect: Making definitional issues an explicit methodological concern

In the United States, research on child abuse and neglect is frequently criticized for being poorly performed and largely irrelevant to the important policy questions facing the field. Many of the problems plaguing research on child abuse and neglect are endemic to social science research generally, and this paper does not trod over such issues, which are well known and well described elsewhere. Instead, this paper describes how the inadequacy of definitions of “child abuse” and “child neglect” used by research studies places an additional—and largely unnoticed—burden on research, which aggravates the impact of these more general problems. Existing definitions of “child abuse” and “child neglect” fail to meet research needs because they lack: (1) comparability, (2) reliability, and (3) taxonomic delineation. As a result, they compromise the findings of incidence studies, sequelae studies, etiological studies, and program effectiveness studies. Therefore, if real progress is to be made in understanding child abuse and neglect, definitional issues must become an explicit methodological concern. Specifically, future research should include: (I) a careful determination of definitional needs, (2) the development of operational definitions to meet those needs, and (3) the circumspect statement of findings based on the limitations imposed by such definitions.     

Why might relative fit indices differ between estimators?

Previous research indicates that relative fit indices in structural equation modeling may vary across estimation methods. Sugawara and MacCallum (1993) explained that the discrepancy arises from difference in the function values for the null model with no further derivation given. In this study, we derive explicit solutions for parameters of the null model. The null model specifies the variances of the observed variables as model parameters and fixes all the covariances to be zero. Three methods of estimation are considered: the maximum likelihood (ML) method, the ordinary least squares (OLS) method, and the generalized least squares (GLS) method. Results indicate that ML and LS yield an identical estimator, which is different from GLS. Function values and associated chi‐square statistics of the null model vary across estimation methods. Consequently, relative fit indices using the null model as the reference point in computation may yield different results depending on the estimation method chosen. An illustration example is given and implications of this study are discussed.     

Performance effects of partnership between manufacturers and suppliers for new product development: the supplier’s standpoint

This study analyzes the effects of supplier involvement in a manufacturer’s new product development on the supplier’s financial performance, innovation, and product quality with data from 128 suppliers in the Korean automobile and electronics industries. The results indicate that a higher level of supplier’s involvement positively influences innovation and financial performance. The results generally indicate that a higher level of supplier involvement, especially in the form of involvement in the design stage significantly increases suppliers’ innovation and cash-flow rate. However, the positive effect of supplier involvement on quality was observed only in the electronics industry.     

Student outcomes of the physical education and physical literacy (PEPL) approach: a pragmatic cluster randomised controlled trial of a multicomponent intervention to improve physical literacy in primary schools

ABSTRACT

Background: Health organisations such as the United Nations continue to place an expectation on school physical education (PE) programmes and wider school strategies to ensure students develop physical literacy and receive the well-established benefits of meeting physical activity guidelines. Barriers to meet this expectation such as lack of trained PE teachers, lack of time and greater emphasis on academic achievement are ongoing challenges to schools. The purpose of this study was to evaluate the impact of the multi-component Physical Education Physical Literacy (PEPL) intervention, designed to improve students’ fundamental movement skill, perceived physical abilities and level of physical activity.

Method: A qualified PE teacher implemented the PEPL intervention across seven schools, and another seven schools formed a control group as part of a randomised cluster-based trial. Grade 5 students (N?=?318, age 10.4 years?±?SD 0.4) completed assessments of physical activity, fundamental movement skill, attitudes towards PE, and self-perceptions of physical abilities before and after a 33-week intervention. Intervention effects were examined using general linear mixed models. Post-intervention focus groups with students were used to develop insights into experiences and outcomes.

Results: With no significant gender interactions, the PEPL approach led to enhanced object control skills (β?=?1.62; SE?=?0.61; p?=?0.008), with little evidence of any other fundamental movement skill improvements in excess of those in the control group. There was also modest evidence for an effect on accelerometer measured moderate-to-vigorous physical activity (MVPA) during school time (β?=?4.50; SE?=?2.39; p?=?0.058), but this was not accompanied by any significant intervention effect over the entire week. Questionnaires indicated students in the PEPL programme became less satisfied with their own sporting ability (β?=??0.20; SE?=?0.08; p?=?0.013) but qualitative data analyses suggested that they enjoyed the PEPL approach experience, becoming more motivated and confident in their physical abilities.

Conclusions: Evidence of enhanced object control skill, increased confidence and motivation to be physically active, and moderate evidence of more MVPA during school time, indicate that the introduction of the PEPL approach contributed to the development of student physical literacy. A decrease in perceived sporting competence warrants greater attention on student’s self-perceptions in future iterations of the intervention.

Trial registration: Australian New Zealand Clinical Trials Registry identifier: ACTRN12615000066583.     

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