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.     

The superstar phenomenon in the knowledge management and intellectual capital academic discipline

This paper reports on the first documented attempt to investigate the presence of the superstar (or Matthew) effect in the knowledge management and intellectual capital (KM/IC) scholarly discipline. The Yule–Simon model and Lotka's square law were applied to the publication data obtained from 2175 articles from 11 KM/IC journals. Based on the findings, it was concluded that the KM/IC discipline represents a very young, attractive academic field that welcomes contributions from a variety of academics and practitioners. In their paper acceptance decisions, KM/IC journal editors are not biased towards a small group of highly productive researchers, which is a positive sign that the field has been progressing in the right direction. The discipline is driven more by academics than by practitioners, and the distribution of articles is more concentrated among a few academic but not practitioner institutions. It was also observed that the Yule–Simon model and Lotka's square law may produce different distributions with respect to institutions.     

The validity of performance assessments for teacher licensure: Connecticut''s ongoing research

This article was based on a paper presented at the annual meeting of the American Educational Research Association, San Francisco, March 27 to March 31, 1989.     

Pictorial organization in prose learning

Ninety undergraduates of high and low prior knowledge of geology read a difficult prose passage concerning the formation of a meander. Two groups of learners were forced to process a map-like organizer either before or after they read the passage, while a control group was provided no pictorial support. The results showed that subjects with little prior knowledge who were provided with the organizer prior to reading recalled at a level similar to that of subjects with a good deal of background knowledge. The findings were interpreted as support for the use of map-like organizers in the primary position to aid comprehension.     

THE IMPACT OF HISTORY,GEOGRAPHY, AND THE ECONOMY ON HIGHER EDUCATION POLICY: A COMPARATIVE SURVEY

Confronted with the rapid development of higher education in this century but particularly over the last twenty years, the author identifies a number of factors influencing this development and estimates their relative importance. The factors which he lists includes economic and technological factors, demographic factors, geographical factors, historical and political factors, and cultural and ‐ religious factors. The interplay of these factors over time and space leads to the diversification of higher education which in turn raises the major question of how diversification is to be regulated. This major question then leads to more specific questions related to the funding of higher education, the development of such forms as adult and continuing education, the guarantee of equal opportunity, the mobility of students and teachers, the link between higher education and employment, and the ways in which higher education can influence actors in the political arena to act in its favour.     

The Cambridge B.Ed.

This article was written in January 1970 for The Cambridge Review and appeared in the issue of 29 May 1970. The author had University readers chiefly in mind; the stress would have been differently placed had it been written in the first place for the present journal, but it seemed best to keep the article in its original form apart from small corrections. It is printed here with the kind permission of the Editors of the Review.