Programmed sample delivery on a pressurized paper

This paper reports a method to control the fluid flow in paper-based microfluidic devices simply by pressing over the channel surface of paper, thereby decreasing the pore size and permeability of a non-woven polypropylene sheet. As a result, fluid resistance is increased in the pressed region and causes flow rate to decrease. We characterize the decrease of flow rate with respect to different amounts of pressure applied, and up to 740% decrease in flow velocity was achieved. In addition, we demonstrate flow rate control in a Y-shaped merging paper and sequential delivery of multiple color dyes in a three-branched paper. Furthermore, sequential delivery of multiple fluid samples is performed to demonstrate its application in multi-step colorimetric immunoassay, which shows a 4.3-fold signal increase via enhancement step.     

Optofluidic microvalve-on-a-chip with a surface plasmon-enhanced fiber optic microheater

We present an optofluidic microvalve utilizing an embedded, surface plasmon-enhanced fiber optic microheater. The fiber optic microheater is formed by depositing a titanium thin film on the roughened end-face of a silica optical fiber that serves as a waveguide to deliver laser light to the titanium film. The nanoscale roughness at the titanium-silica interface enables strong light absorption enhancement in the titanium film through excitation of localized surface plasmons as well as facilitates bubble nucleation. Our experimental results show that due to the unique design of the fiber optic heater, the threshold laser power required to generate a bubble is greatly reduced and the bubble growth rate is significantly increased. By using the microvalve, stable vapor bubble generation in the microchannel is demonstrated, which does not require complex optical focusing and alignment. The generated vapor bubble is shown to successfully block a liquid flow channel with a size of 125 μm × 125 μm and a flow rate of ∼10 μl/min at ∼120 mW laser power.     

Being Black, Male, and Gifted in Miami: Prevalence and Predictors of Placement in Elementary School Gifted Education Programs

Although it is well established that Black male students are underrepresented in gifted educational programs in the United States, due to a scarcity of longitudinal prospective research, little is known about the protective factors at the child, family, and school level that increase the probability of Black male students being identified as gifted during early elementary school. Using data from the Miami School Readiness Project, we followed 6,926 low-income Black males from preschool through 5th grade to describe trajectories for the 453 Black males (6.5 %) who were identified as gifted, and examined child, family, and preschool variables associated with gifted classification. Boys were most commonly identified as gifted in first and second grade, and 15 % of the identified boys did not appear to be receiving gifted courses. Hierarchical multiple logistic regression analyses revealed that being classified as gifted in early elementary school was more likely for Black males who (a) attended public school pre-K programs at age four, (b) had higher cognitive, language, fine motor, behavioral, and emergent literacy school readiness skills before entering kindergarten, (c) spoke a language other than English at home, (d) were older upon entering kindergarten, (e) received higher grades in school, and (f) scored higher on standardized tests of math and reading. Predictors of gifted identification in the kindergarten year were different and weaker compared to identification in later years. Implications for early identification and intervention for talented Black males are discussed.     

The use of school self‐evaluation results in the Netherlands and Flanders

This article presents the results of two studies on the use of school self‐evaluation in the Netherlands and Flanders. It focuses on which forms of instrumental use of school self‐evaluation results can be found in schools, and how differences in self‐evaluation use between schools can be explained. Results show that the instrumental use of self‐evaluation results in both contexts was limited. Results further show that differences in the use of school self‐evaluation results can be explained by differences in school organizational characteristics, implementation characteristics, and the characteristics of the school self‐evaluation itself. Implications for theory, policy, and practice are discussed.     

Measurement Invariance Testing with Many Groups: A Comparison of Five Approaches

With the increasing use of international survey data especially in cross-cultural and multinational studies, establishing measurement invariance (MI) across a large number of groups in a study is essential. Testing MI over many groups is methodologically challenging, however. We identified 5 methods for MI testing across many groups (multiple group confirmatory factor analysis, multilevel confirmatory factor analysis, multilevel factor mixture modeling, Bayesian approximate MI testing, and alignment optimization) and explicated the similarities and differences of these approaches in terms of their conceptual models and statistical procedures. A Monte Carlo study was conducted to investigate the efficacy of the 5 methods in detecting measurement noninvariance across many groups using various fit criteria. Generally, the 5 methods showed reasonable performance in identifying the level of invariance if an appropriate fit criterion was used (e.g., Bayesian information criteron with multilevel factor mixture modeling). Finally, general guidelines in selecting an appropriate method are provided.     

Unfolding Case‐Based Practicum Curriculum Infusing Crisis,Trauma, and Disaster Preparation

The authors evaluated an unfolding case‐based approach to a practicum in counseling course infusing crisis, trauma, and disaster preparation for changes in students’ crisis self‐efficacy across a semester. The course, informed by constructivist‐developmental pedagogy and centered on the unfolding case, resulted in significant increases in students’ crisis self‐efficacy.     

Doing good while performing well at Flemish universities: benchmarking higher education institutions in terms of social inclusion and market performance

Universities, and higher education institutions in general, are ever more influenced by output-driven performance indicators and models that originally stem from the profit-organisational context. As a result, universities are increasingly considering management tools that support them in the (decision) process for attaining their strategic goals. The growth-share matrix is one of these tools that has proven its value in diverse business and competitive contexts in the past few decades. The present study’s contribution is twofold. First, we apply and interpret the growth-share matrix as part of a strategic positioning analysis in a strategic university context. Second, we extend this tool by incorporating social inclusion as a third dimension in the analysis. In recent years, discussions on the rising social disparity among adolescents in higher education have increased and different types of actors have raised the motivation to create more equal opportunities for prospective students who rank among the group of socially disadvantaged adolescents. The findings of an empirical case of the proposed model for a particular Belgian academic programme show that increased social inclusion and higher performance parameters, such as growth in student enrolments and diplomas, can be reached simultaneously.     

<Emphasis Type="Italic">Agrobacterium</Emphasis>-mediated transformation of herbicide resistance in creeping bentgrass and colonial bentgrass

Embryogenic calli were induced from the seeds of creeping bentgrass (Agrostis palustris Huds.) cv. Regent and colonial bentgrass (Agrostis Tenuis Sibth. Fl. Oxen.) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4–7 days and then co-cultivated withAgrobacterium tumefaciens, LBA4404. which contains plasmid vector-pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding region and matrix attachment region (MAR). After 3 days of co-cultivation, the calli were washed thoroughly and transferred to MS medium containing 2 mg/L of 2, 4-D, 12–15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2–3 months of selection, the actively growing calli of ‘Regent’ and ‘Tiger’ were transferred to MS medium with 12–15 mg/L PPT and 250 mg/L cefotazime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4% of herbicide Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants and its absence in a randomly selected control plant.     

Examining the Efficacy of Targeted Component Interventions on Language and Literacy for Third and Fourth Graders Who are at Risk of Comprehension Difficulties

Testing a component model of reading comprehension in a randomized controlled trial, we evaluated the efficacy of 4 interventions that were designed to target components of language and metacognition that predict children’s reading comprehension: vocabulary, listening comprehension, comprehension of literate language, academic knowledge, and comprehension monitoring. Third- and 4th-graders with language skills falling below age expectations participated (N = 645). Overall, the component interventions were only somewhat effective in improving the targeted skills, compared to a business-as-usual control (g ranged from ?.14 to .33), and no main effects were significant after correcting for multiple comparisons. Effects did not generalize to other language skills or to students’ reading comprehension. Moreover, there were Child Characteristic × Treatment interaction effects. For example, the intervention designed to build sensorimotor mental representations was more effective for children with weaker vocabulary skills. Implications for component models of reading and interventions for children at risk of reading comprehension difficulties are discussed.