Manipulating particle trajectories with phase-control in surface acoustic wave microfluidics

We present a 91 MHz surface acoustic wave resonator with integrated microfluidics that includes a flow focus, an expansion region, and a binning region in order to manipulate particle trajectories. We demonstrate the ability to change the position of the acoustic nodes by varying the electronic phase of one of the transducers relative to the other in a pseudo-static manner. The measurements were performed at room temperature with 3 μm diameter latex beads dispersed in a water-based solution. We demonstrate the dependence of nodal position on pseudo-static phase and show simultaneous control of 9 bead streams with spatial control of −0.058 μm/deg ± 0.001 μm/deg. As a consequence of changing the position of bead streams perpendicular to their flow direction, we also show that the integrated acoustic-microfluidic device can be used to change the trajectory of a bead stream towards a selected bin with an angular control of 0.008 deg/deg ± 0.000(2) deg/deg.     

Subskill mastery among elementary and middle school students at risk in mathematics

In the present study, we evaluated the number of attempts required to master specific subskills for working with whole and rational numbers among students at risk for math difficulties. Participants included a subset of students in grades four through eight receiving supplemental math support. Mastery—defined as 85% correct on short tests—was assessed following instruction for each subskill. Using survival analysis, we evaluated the number of attempts required to reach a .50 and a .90 probability of mastery on each subskill. The number of required attempts varied across subskills, with many subskills requiring more than one attempt to demonstrate mastery. Further, some of the most difficult content was aligned with curricular standards below students’ grade level. Thus, among students identified for supplemental support, it may be worthwhile to remediate select subskills that fall outside of the grade‐level curriculum before providing additional instruction on grade‐level content. Implications for math subskill assessment and remediation are discussed along with limitations and directions for future research.     

God and Man at Yali College: the short,troubled history of an American College in China

ABSTRACT

Yali College, a four-year institution operating under the aegis of Yale University, offered a US-style undergraduate education in China’s Hunan province from 1914 to 1927. It developed a robust curriculum and an impressive physical plant but collapsed after a little more than a decade. This paper, drawing on new archival research, focuses on the circumstances leading to that collapse. It argues that a deep divide emerged over Yali’s form and function, pitting modernisers at the institution’s helm against its tradition-minded faculty and trustees, eventually crippling the college. The case of Yali helps us understand the perils of ideological misalignment in education, especially when it occurs in challenging sociopolitical contexts like 1920s China.     

Improving Elementary Grade Students’ Science and Social Studies Vocabulary Knowledge Depth,Reading Comprehension,and Argumentative Writing: a Conceptual Replication

Educational Psychology Review - This experimental study aimed to replicate and extend a previous efficacy study of an elementary grade content literacy intervention that demonstrated positive...     

The Paradox of HBCU Graduation Rates

This paper examines the propensity of African American students to graduate from Historically Black Colleges and Universities (HBCUs). Using IPEDS data from 2004 to 2016, we take care in developing a control group of institutions from which to compare HBCU success. Results suggest that despite accepting more students who are at risk of not graduating, HBCUs have a higher graduation rate for African American students than their peers. We then show that gender nor major choice help explain this persistent difference.

     

Complexity in Science Learning: Measuring the Underlying Dynamics of Persistent Mistakes

Abstract

Mistaken beliefs pose a barrier to science learning. For this reason, it is important to understand the circumstances in which they emerge and change. In the current paper, we apply complexity theory to shed light on the nature of mistaken beliefs. The strength of this approach lies in conceptualizing beliefs as dynamic stabilities, a well-defined construct that can be indexed precisely. For example, Recurrence Quantification Analysis (RQA) can determine the presence of dynamic stabilities by analyzing variability in time-series data. We applied this analytical tool to probe for mistaken beliefs in a beam-balancing task, a task that is known to elicit mistaken beliefs in preschoolers. Using a case-study design with four preschoolers, we tracked children’s hand position with motion sensors as they balanced various beams. The resulting time series of hand position was submitted to RQA, yielding two important results: First, we found that consistent mistakes in trying to balance the beams were not always accompanied by dynamic stability. This undermines the common assumption that overt consistency in task performance is sufficient to conclude the presence of beliefs. Second, we found strong individual differences over time, as children explored the balance beams. Applications to science education are discussed.

• Highlights

• A classical task of beam balancing was used to explore the underlying dynamics of children’s mistaken beliefs.

• Moment-to-moment hand movements were tracked and subjected to a multi-dimensional recurrence quantification analysis (RQA).

• Dynamic stability was captured through percent laminarity (%LAM), a measure of rigidity in children’s explorations.

• The RQA measure of %LAM shed light on patterns of stability that were not available from the analysis of overt behavior.

• In line with complexity theory, a model of persistent mistakes is offered that has important implications for science education.

     

The “Batman Effect”: Improving Perseverance in Young Children

This study investigated the benefits of self‐distancing (i.e., taking an outsider's view of one's own situation) on young children's perseverance. Four‐ and 6‐year‐old children (N = 180) were asked to complete a repetitive task for 10 min while having the option to take breaks by playing an extremely attractive video game. Six‐year‐olds persevered longer than 4‐year‐olds. Nonetheless, across both ages, children who impersonated an exemplar other—in this case a character, such as Batman—spent the most time working, followed by children who took a third‐person perspective on the self, or finally, a first‐person perspective. Alternative explanations, implications, and future research directions are discussed.     

The State of Peer Review in Criminology: Literary Theory,Perceptions, and the Catch-22 Metaphor of Peer Review

Considerable theoretical and empirical attention has been devoted to the practice of peer review across various disciplines in the previous couple decades. Recently, Raymond Paternoster and Robert Brame indicated that it is necessary for criminology to follow suit and begin to provide a critical inquiry of the blind review model. Literary theory and writing studies have examined literate practices for decades and empirical research has identified that literate practices, like peer review, are interactional and co-constructed across discourse communities. The unique character of peer review in criminology remains unknown however. Discussions with 40 of criminology’s most influential scholars provides an opportunity to begin constructing a broad context of criminology’s peer review by challenging universal knowledge through individual experiences.     

Film Biographies

A PRIVATE VIEW by Irene Mayer Selznick (New York: Alfred A. Knopf, 1983---$16.95)

A PASSION FOR FILMS: HENRI LANGLOIS AND THE CINEMATHEQUE FRANCAISE (New York: The Viking Press, 1983---$16.95)

MOVIE STAR: A LOOK AT THE WOMEN WHO MADE HOLLYWOOD by Ethan Mordden (New York: St. Martin's Press, 1983---$19.95)     

The gamework

This article outlines the gamework, a neologism designed to help scholars attend to the various kinds of work involved in computer game development, play and analysis. This work is integral to computer game artifactuality yet tends to be obscured by the aesthetic, narratological, mechanical, and economic aspects of games and gaming. We offer the gamework as a means for theorizing computer games as a form of culture that motivates work as much as (if not more than) play. Specifically, we point to how computer games participate in (1) labor culture; (2) an emergent culture determined by a work/labor/play dialectic; (3) artistic culture; and (4) cultural criticism.