Migration distance-based platelet function analysis in a microfluidic system

Aggregation and adhesion of platelets to the vascular wall are shear-dependent processes that play critical roles in hemostasis and thrombosis at vascular injury sites. In this study, we designed a simple and rapid assay of platelet aggregation and adhesion in a microfluidic system. A shearing mechanism using a rotating stirrer provided adjustable shear rate and shearing time and induced platelet activation. When sheared blood was driven through the microchannel under vacuum pressure, shear-activated platelets adhered to a collagen-coated surface, causing blood flow to significantly slow and eventually stop. To measure platelet adhesion and aggregation, the migration distance (MD) of blood through the microchannel was monitored. As the microstirrer speed increased, MD initially decreased exponentially but then increased beyond a critical rpm. For platelet-excluded blood samples, there were no changes in MD with increasing stirrer speed. These findings imply that the stirrer provided sufficiently high shear to activate platelets and that blood MD is a potentially valuable index for measuring the shear-dependence of platelet activation. Our microfluidic system is quick and simple, while providing a precise assay to measure the effects of shear on platelet aggregation and adhesion.     

Reading-growth estimates for elementary-school students using curriculum-based measurement

In this study, we examine grade-level growth rates for general education students and students with learning disabilities in grades two to six. In conducting the study, we demonstrate how schools, districts, and state educational agencies can use a combination of Curriculum-Based Measurement and Hierarchical Linear Modeling (HLM) methods to develop growth-rate norms in reading. The participants were made up of 273 general education students and 430 students with learning disabilities. The growth rates for these two groups of students in each grade were estimated using HLM. Within each grade, separate growth rates for subgroups of general education students (i.e., high, average, and low achievers) were estimated. The uses of estimated growth rates for setting year-end goals, monitoring student progress, and evaluating the effectiveness of instructional programs are also discussed.     

Effects of different types of instructor comments in online discussions

The current study examined the effects of different types of instructor comments on student engagement in an online discussion. In particular, this study examined three comment types: (1) praise-oriented comments, agreeing with students’ initial messages and recapping their ideas, (2) elaboration-encouraging comments, requesting elaboration on the initial messages, and (3) perspective-widening comments, suggesting different or thought-provoking opinions responding to the initial messages. Seventeen graduate students enrolled in an online course were recruited. A content analysis was employed to evaluate the levels of knowledge construction. Interactivity was measured by the number of posts and idea units. The findings revealed that perspective-widening comments facilitated students’ evaluation on the peer postings and brought up diverse perspectives, contributing to knowledge construction. While elaboration-encouraging comments led to high interactivity among students, praise-oriented comments had no significant effect on the frequency of interactivity.     

Fertility, relative wages, and labor market decisions: A case of female teachers

This paper examines the effects of fertility and relative wages on occupational choice (teaching versus non-teaching) and labor force participation decisions of female college graduates using selectivity-corrected panel estimations.We find that the presence of a new born baby is not particularly important to the choice of occupation, but significantly discourages female labor force participation, especially among teachers. Higher relative wages are found to effectively attract female college graduates into teaching. College major in education is one of the most relevant determinants for female college graduates to become teachers. Though investing educational expenditures on teachers’ salary seems to be a valid policy, providing incentives for female college students to major in education will be an alterative way to secure teacher supply.     

Curriculum-based measurement in the content areas: vocabulary matching as an indicator of progress in social studies learning

The purpose of this study was to examine the reliability and validity of curriculum-based measures as indicator of growth in content-area learning. Participants were 58 students in 2 seventh-grade social studies classes. CBM measures were student- and administrator-read vocabulary-matching probes. Criterion measures were performance on a knowledge test, the social studies subtest of the Iowa Test of Basic Skills (ITBS), and student grades. Both the student- and examiner-read measures reflected change in performance; however, only the student-read measure resulted in interindividual differences in growth rates. Significant relations were found between the growth rates generated by the student-read vocabulary measure and student course grades, ITBS scores, and growth on the knowledge test. These results support the validity of a vocabulary-matching measure as an indicator of student learning in the content areas. The results are discussed in terms of the use of CBM as a system for monitoring performance and evaluating interventions for students with learning disabilities in content-area classrooms.     

Tutoring styles that encourage learner satisfaction,academic engagement,and achievement in an online environment

This study was aimed to find which tutoring styles significantly predict learners’ satisfaction with an e-learning service, academic involvement, and academic achievement. The tutoring styles included subject expert, facilitator, guider, and administrator. In this study, 818 Korean sixth-grade students (ages 11–12 years), enrolled in the e-study program, and completed tutoring style and academic satisfaction evaluation surveys. Students’ login and posting frequency in the e-study program were measured to assess their academic involvement. Academic achievement was computed using completion rates and assessment scores. Multiple regression analyses indicated that there is some association between tutoring styles and academic outcomes. Of the four tutoring styles, facilitating tutoring styles particularly showed strong associations with the three outcome variables. Tutors’ guiding activities as opposed to facilitating were not significant contributors to students’ academic outcomes. The effect of tutors’ facilitating styles in an online learning environment was significant as being found in the existent literature.     

Examining the hard,peer, and teacher scaffolding framework in inquiry-based technology-enhanced learning environments: impact on academic achievement and group performance

Educational technology research and development - The purpose of this study was to examine how students’ academic achievement and group performance related to their perceptions of the...     

The triarchic theory of intelligence and computer-based inquiry learning

Sternberg's (1985) triarchic theory of human intelligence distinguished among three types of intellectual abilities: analytic, creative, and practical. Our study explored the relationships between student abilities and the cognitive and attitudinal outcomes that resulted from student immersion in a computer-based inquiry environment. In particular, we examined outcome variables related to content understanding, problem solving, and science-related attitudes. Results indicated that more practical abilities predicted greater content understanding and transfer of problem-solving skills. High analytic abilities were predictive of content understanding but not transfer of problem-solving skills. High creative abilities predicted problem solving, but were not predictive of performance on content understanding. In terms of science-related attitudes, students who were dominant in practical abilities had significantly more positive posttest attitudes than those dominant in analytic abilities. The results from this study were used to make recommendations regarding design principles used in the subsequent development of computer-based inquiry environments.